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_ATOM_SITE_[]
CIF
Data items in the ATOM_SITE category record details about
the atom sites in a crystal structure, such as the positional coordinates, atomic displacement parameters, and magnetic moments and directions.
Examples:
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_calc_flag
_atom_site_calc_attached_atom
O1 .4154(4) .5699(1) .3026(0) .060(1) Uani ? ?
C2 .5630(5) .5087(2) .3246(1) .060(2) Uani ? ?
C3 .5350(5) .4920(2) .3997(1) .048(1) Uani ? ?
N4 .3570(3) .5558(1) .4167(0) .039(1) Uani ? ?
C5 .3000(5) .6122(2) .3581(1) .045(1) Uani ? ?
O21 .6958(5) .4738(2) .2874(1) .090(2) Uani ? ?
C31 .4869(6) .3929(2) .4143(2) .059(2) Uani ? ?
# - - - - data truncated for brevity - - - -
H321C .04(1) .318(3) .320(2) .14000 Uiso ? ?
H322A .25(1) .272(4) .475(3) .19000 Uiso ? ?
H322B .34976 .22118 .40954 .19000 Uiso calc C322
H322C .08(1) .234(4) .397(3) .19000 Uiso ? ?
loop_
_atom_site_aniso_label
_atom_site_aniso_B_11
_atom_site_aniso_B_22
_atom_site_aniso_B_33
_atom_site_aniso_B_12
_atom_site_aniso_B_13
_atom_site_aniso_B_23
_atom_site_aniso_type_symbol
O1 .071(1) .076(1) .0342(9) .008(1) .0051(9) -.0030(9) O
C2 .060(2) .072(2) .047(1) .002(2) .013(1) -.009(1) C
C3 .038(1) .060(2) .044(1) .007(1) .001(1) -.005(1) C
N4 .037(1) .048(1) .0325(9) .0025(9) .0011(9) -.0011(9) N
C5 .043(1) .060(1) .032(1) .001(1) -.001(1) .001(1) C
# - - - - data truncated for brevity - - - -
O21 .094(2) .109(2) .068(1) .023(2) .038(1) -.010(1) O
C51 .048(2) .059(2) .049(1) .002(1) -.000(1) .007(1) C
C511 .048(2) .071(2) .097(3) -.008(2) -.003(2) .010(2) C
C512 .078(2) .083(2) .075(2) .009(2) -.005(2) .033(2) C
C513 .074(2) .055(2) .075(2) .004(2) .001(2) -.010(2) C
# - - - - data truncated for brevity - - - -
loop_
_atom_site_label
_atom_site_chemical_conn_number
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
S1 1 0.74799(9) -0.12482(11) 0.27574(9) 0.0742(3)
S2 2 1.08535(10) 0.16131(9) 0.34061(9) 0.0741(3)
N1 3 1.0650(2) -0.1390(2) 0.2918(2) 0.0500(5)
C1 4 0.9619(3) -0.0522(3) 0.3009(2) 0.0509(6)
# - - - - data truncated for brevity - - - -
loop_
_atom_site_label # *_assembly 'M' is a disordered methyl
_atom_site_occupancy # with configurations 'A' and 'B':
_atom_site_disorder_assembly #
_atom_site_disorder_group # H11B H11A H13B
# . | .
C1 1 . . # . | .
H11A .5 M A # . | .
H12A .5 M A # C1 --------C2---
H13A .5 M A # / . \
H11B .5 M B # / . \
H12B .5 M B # / . \
H13B .5 M B # H12A H12B H13A
_atom_site_adp_type
CIF
A standard code used to describe the type of atomic displacement
parameters used for the site.
_atom_site_aniso_B
CIF
Data names: _atom_site_aniso_B_11 _atom_site_aniso_B_12 _atom_site_aniso_B_13 _atom_site_aniso_B_22 _atom_site_aniso_B_23 _atom_site_aniso_B_33
These are the standard anisotropic atomic displacement
components in angstroms squared which appear in the structure-factor term
T = exp{-(1/4) sum~i~ [ sum~j~ (B^ij^ h~i~ h~j~ a*~i~ a*~j~) ] }
h = the Miller indices a* = the reciprocal-space cell lengths
The unique elements of the real symmetric matrix are entered by row.
The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred.
_atom_site_aniso_label
CIF
Anisotropic atomic displacement parameters are usually looped in
a separate list. If this is the case, this code must match the _atom_site_label of the associated atom in the atom coordinate list and conform with the same rules described in _atom_site_label.
_atom_site_aniso_ratio
CIF
Ratio of the maximum to minimum principal axes of
displacement (thermal) ellipsoids.
_atom_site_aniso_type_symbol
CIF
This _atom_type_symbol code links the anisotropic atom
parameters to the atom-type data associated with this site and
must match one of the _atom_type_symbol codes in this list.
_atom_site_aniso_U
CIF
Data names: _atom_site_aniso_U_11 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_22 _atom_site_aniso_U_23 _atom_site_aniso_U_33
These are the standard anisotropic atomic displacement
components in angstroms squared which appear in the structure-factor term
T = exp{-2pi^2^ sum~i~ [sum~j~ (U^ij^ h~i~ h~j~ a*~i~ a*~j~) ] }
h = the Miller indices a* = the reciprocal-space cell lengths
The unique elements of the real symmetric matrix are entered by row.
_atom_site_attached_hydrogens
CIF
The number of hydrogen atoms attached to the atom at this site
excluding any hydrogen atoms for which coordinates (measured or calculated) are given.
Examples:
2
1
4
_atom_site_B_equiv_geom_mean
CIF
Equivalent isotropic atomic displacement parameter, B(equiv),
in angstroms squared, calculated as the geometric mean of the anisotropic atomic displacement parameters.
B(equiv) = (B~i~ B~j~ B~k~)^1/3^
B~n~ = the principal components of the orthogonalized B^ij^
The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred.
_atom_site_B_iso_or_equiv
CIF
Isotropic atomic displacement parameter, or equivalent isotropic
atomic displacement parameter, B(equiv), in angstroms squared, calculated from anisotropic displacement components.
B(equiv) = (1/3) sum~i~[sum~j~(B^ij^ a*~i~ a*~j~ a~i~ a~j~)]
a = the real-space cell lengths a* = the reciprocal-space cell lengths B^ij^ = 8 pi^2^ U^ij^
Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44,
775-776.
The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred.
_atom_site_calc_attached_atom
CIF
The _atom_site_label of the atom site to which the 'geometry-
calculated' atom site is attached.
_atom_site_calc_flag
CIF
A standard code to signal whether the site coordinates have been
determined from the intensities or calculated from the geometry of surrounding sites, or have been assigned dummy coordinates. The abbreviation 'c' may be used in place of 'calc'.
_atom_site_Cartn
CIF
Data names: _atom_site_Cartn_x _atom_site_Cartn_y _atom_site_Cartn_z
The atom-site coordinates in angstroms specified according to a
set of orthogonal Cartesian axes related to the cell axes as
specified by the _atom_sites_Cartn_transform_axes description.
_atom_site_chemical_conn_number
CIF
This number links an atom site to the chemical connectivity list.
It must match a number specified by _chemical_conn_atom_number.
_atom_site_constraints
CIF
A description of the constraints applied to parameters at this
site during refinement. See also _atom_site_refinement_flags and _refine_ls_number_constraints.
Example:
pop=1.0-pop(Zn3)
_atom_site_description
CIF
A description of special aspects of this site. See also
_atom_site_refinement_flags.
Example:
Ag/Si disordered
_atom_site_disorder_assembly
CIF
A code which identifies a cluster of atoms that show long-range
positional disorder but are locally ordered. Within each such
cluster of atoms, _atom_site_disorder_group is used to identify
the sites that are simultaneously occupied. This field is only
needed if there is more than one cluster of disordered atoms
showing independent local order.
Examples:
A
B
S
_atom_site_disorder_group
CIF
A code which identifies a group of positionally disordered atom
sites that are locally simultaneously occupied. Atoms that are positionally disordered over two or more sites (e.g. the hydrogen atoms of a methyl group that exists in two orientations) can be assigned to two or more groups. Sites belonging to the same group are simultaneously occupied, but those belonging to different groups are not. A minus prefix (e.g. "-1") is used to indicate sites disordered about a special position.
Examples:
1
2
-1
_atom_site_fract
CIF
Data names: _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z
Atom-site coordinates as fractions of the _cell_length_ values.
_atom_site_label
CIF
The _atom_site_label is a unique identifier for a particular site
in the crystal. This code is made up of a sequence of up to seven components, _atom_site_label_component_0 to *_6, which may be specified as separate data items. Component 0 usually matches one of the specified _atom_type_symbol codes. This is not mandatory if an _atom_site_type_symbol item is included in the atom-site list. The _atom_site_type_symbol always takes precedence over an _atom_site_label in the identification of the atom type. The label components 1 to 6 are optional, and normally only components 0 and 1 are used. Note that components 0 and 1 are concatenated, while all other components, if specified, are separated by an underscore. Underscores are only used if higher-order components exist. If an intermediate component is not used, it may be omitted provided the underscore separators are inserted. For example, the label 'C233__ggg' is acceptable and represents the components C, 233, '' and ggg. Different labels may have a different number of components.
Examples:
C12
Ca3g28
Fe3+17
H*251
boron2a
C_a_phe_83_a_0
Zn_Zn_301_A_0
_atom_site_label_component
CIF
Data names: _atom_site_label_component_0 _atom_site_label_component_1 _atom_site_label_component_2 _atom_site_label_component_3 _atom_site_label_component_4 _atom_site_label_component_5 _atom_site_label_component_6
Component 0 is normally a code which matches identically with
one of the _atom_type_symbol codes. If this is the case, then the rules governing the _atom_type_symbol code apply. If, however, the data item _atom_site_type_symbol is also specified in the atom-site list, component 0 need not match this symbol or adhere to any of the _atom_type_symbol rules. Component 1 is referred to as the "atom number". When component 0 is the atom-type code, it is used to number the sites with the same atom type. This component code must start with at least one digit which is not followed by a + or - sign (to distinguish it from the component 0 rules). Components 2 to 6 contain the identifier, residue, sequence, asymmetry identifier and alternate codes, respectively. These codes may be composed of any characters except an underscore.
_atom_site_occupancy
CIF
The fraction of the atom type present at this site.
The sum of the occupancies of all the atom types at this site may not significantly exceed 1.0 unless it is a dummy site. The value must lie in the 99.97% Gaussian confidence interval -3u =< x =< 1 + 3u. The _enumeration_range of 0.0:1.0 is thus correctly interpreted as meaning (0.0 - 3u) =< x =< (1.0 + 3u).
_atom_site_refinement_flags
CIF
A concatenated series of single-letter codes which indicate the
refinement restraints or constraints applied to this site. This
item should not be used. It has been replaced by
_atom_site_refinement_flags_posn, *_adp and *_occupancy. It is
retained in this dictionary only to provide compatibility with
legacy CIFs.
_atom_site_refinement_flags_adp
CIF
A code which indicates the refinement restraints or constraints
applied to the atomic displacement parameters of this site.
_atom_site_refinement_flags_occupancy
CIF
A code which indicates that refinement restraints or
constraints were applied to the occupancy of this site.
_atom_site_refinement_flags_posn
CIF
A code which indicates the refinement restraints or constraints
applied to the positional coordinates of this site.
_atom_site_restraints
CIF
A description of restraints applied to specific parameters at
this site during refinement. See also _atom_site_refinement_flags and _refine_ls_number_restraints.
Example:
restrained to planar ring
_atom_site_site_symmetry_multiplicity
CIF
The number of different sites that are generated by the
application of the space-group symmetry to the
coordinates given for this site. It is equal to the
multiplicity given for this Wyckoff site
in International Tables for Crystallography Vol. A (2002).
It is equal to the multiplicity of the general position
divided by the order of the site symmetry given in
_atom_site_site_symmetry_order.
_atom_site_site_symmetry_order
CIF
The order of the site symmetry of the site identified by
_atom_site_label.
This is the number of times application of the crystallographic symmetry to the coordinates given for this site generates the same set of coordinates. It is equal to:
multiplicity of the general position
------------------------------------
multiplicity of this site
where 'multiplicity of this site' is
given in _atom_site_site_symmetry_multiplicity.
_atom_site_symmetry_multiplicity
CIF
The multiplicity of a site due to the space-group symmetry as
given in International Tables for Crystallography Vol. A (2002).
Use of this data name is deprecated because of inconsistencies in practice among structure refinement software packages. The number of positions given for this Wyckoff site in International Tables for Crystallography Vol. A (2002). should now be expressed using the data name _atom_site_site_symmetry_multiplicity. In the historic archive some CIFs use this item to give values that belong in _atom_site_site_symmetry_order.
_atom_site_thermal_displace_type
CIF
A standard code used to describe the type of atomic displacement
parameters used for the site.
_atom_site_type_symbol
CIF
A code to identify the atom species (singular or plural)
occupying this site. This code must match a corresponding _atom_type_symbol. The specification of this code is optional if component 0 of the _atom_site_label is used for this purpose. See _atom_type_symbol.
Examples:
Cu
Cu2+
dummy
Fe3+Ni2+
S-
H*
H(SDS)
_atom_site_U_equiv_geom_mean
CIF
Equivalent isotropic atomic displacement parameter, U(equiv),
in angstroms squared, calculated as the geometric mean of the anisotropic atomic displacement parameters.
U(equiv) = (U~i~ U~j~ U~k~)^1/3^
U~n~ = the principal components of the orthogonalized U^ij^
_atom_site_U_iso_or_equiv
CIF
Isotropic atomic displacement parameter, or equivalent isotropic
atomic displacement parameter, U(equiv), in angstroms squared, calculated from anisotropic atomic displacement parameters.
U(equiv) = (1/3) sum~i~[sum~j~(U^ij^ a*~i~ a*~j~ a~i~ a~j~)]
a = the real-space cell lengths a* = the reciprocal-space cell lengths
Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44,
775-776.
_atom_site_Wyckoff_symbol
CIF
The Wyckoff symbol (letter) as listed in the space-group tables
of International Tables for Crystallography Vol. A (2002).
_ATOM_SITES_[]
CIF
Data items in the ATOM_SITES category record details about
the crystallographic cell and cell transformations, which are common to all atom sites.
Example:
_atom_sites_Cartn_transform_axes
'c along z, astar along x, b along y'
_atom_sites_Cartn_tran_matrix_11 58.39 _atom_sites_Cartn_tran_matrix_12 0.00 _atom_sites_Cartn_tran_matrix_13 0.00 _atom_sites_Cartn_tran_matrix_21 0.00 _atom_sites_Cartn_tran_matrix_22 86.70 _atom_sites_Cartn_tran_matrix_23 0.00 _atom_sites_Cartn_tran_matrix_31 0.00 _atom_sites_Cartn_tran_matrix_32 0.00 _atom_sites_Cartn_tran_matrix_33 46.27
_atom_sites_Cartn_tran_matrix
CIF
Data names: _atom_sites_Cartn_tran_matrix_11 _atom_sites_Cartn_tran_matrix_12 _atom_sites_Cartn_tran_matrix_13 _atom_sites_Cartn_tran_matrix_21 _atom_sites_Cartn_tran_matrix_22 _atom_sites_Cartn_tran_matrix_23 _atom_sites_Cartn_tran_matrix_31 _atom_sites_Cartn_tran_matrix_32 _atom_sites_Cartn_tran_matrix_33
Matrix elements used to transform fractional coordinates in
the ATOM_SITE category to Cartesian coordinates. The axial
alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is
defined in _atom_sites_Cartn_tran_vector_.
x' |11 12 13| x | 1 |
( y' ) Cartesian = |21 22 23| ( y ) fractional + | 2 |
z' |31 32 33| z | 3 |
_atom_sites_Cartn_tran_vector
CIF
Data names: _atom_sites_Cartn_tran_vector_1 _atom_sites_Cartn_tran_vector_2 _atom_sites_Cartn_tran_vector_3
Elements of a 3 x 1 translation vector used in the
transformation of fractional coordinates in the
ATOM_SITE category to Cartesian coordinates. The axial
alignments of this transformation are described in
_atom_sites_Cartn_transform_axes.
x' |11 12 13| x | 1 |
( y' ) Cartesian = |21 22 23| ( y ) fractional + | 2 |
z' |31 32 33| z | 3 |
_atom_sites_Cartn_transform_axes
CIF
A description of the relative alignment of the crystal cell
axes to the Cartesian orthogonal axes as applied in the transformation matrix _atom_sites_Cartn_tran_matrix_.
Example:
a parallel to x; b in the plane of y and z
_atom_sites_fract_tran_matrix
CIF
Data names: _atom_sites_fract_tran_matrix_11 _atom_sites_fract_tran_matrix_12 _atom_sites_fract_tran_matrix_13 _atom_sites_fract_tran_matrix_21 _atom_sites_fract_tran_matrix_22 _atom_sites_fract_tran_matrix_23 _atom_sites_fract_tran_matrix_31 _atom_sites_fract_tran_matrix_32 _atom_sites_fract_tran_matrix_33
Matrix elements used to transform Cartesian coordinates in
the ATOM_SITE category to fractional coordinates. The axial
alignments of this transformation are described in
_atom_sites_Cartn_transform_axes. The 3 x 1 translation is
defined in _atom_sites_fract_tran_vector_.
x' |11 12 13| x | 1 |
( y' ) fractional = |21 22 23| ( y ) Cartesian + | 2 |
z' |31 32 33| z | 3 |
_atom_sites_fract_tran_vector
CIF
Data names: _atom_sites_fract_tran_vector_1 _atom_sites_fract_tran_vector_2 _atom_sites_fract_tran_vector_3
Elements of a 3 x 1 translation vector used in the
transformation of Cartesian coordinates in the
ATOM_SITE category to fractional coordinates. The axial
alignments of this transformation are described in
_atom_sites_Cartn_transform_axes.
x' |11 12 13| x | 1 |
( y' ) fractional = |21 22 23| ( y ) Cartesian + | 2 |
z' |31 32 33| z | 3 |
_atom_sites_solution_primary
CIF
Codes which identify the methods used to locate the initial
atom sites. The *_primary code identifies how the first atom sites were determined; the *_secondary code identifies how the remaining non-hydrogen sites were located; and the *_hydrogens code identifies how the hydrogen sites were located.
Ref: Sheldrick, G. M., Hauptman, H. A., Weeks, C. M.,
Miller, R. and Usón, I. (2001). Ab initio phasing.
In International Tables for Crystallography,
Vol. F. Crystallography of biological macromolecules,
edited by M. G. Rossmann and E. Arnold, ch. 16.1.
Dordrecht: Kluwer Academic Publishers.
_atom_sites_solution_secondary
CIF
Codes which identify the methods used to locate the initial
atom sites. The *_primary code identifies how the first atom sites were determined; the *_secondary code identifies how the remaining non-hydrogen sites were located; and the *_hydrogens code identifies how the hydrogen sites were located.
Ref: Sheldrick, G. M., Hauptman, H. A., Weeks, C. M.,
Miller, R. and Usón, I. (2001). Ab initio phasing.
In International Tables for Crystallography,
Vol. F. Crystallography of biological macromolecules,
edited by M. G. Rossmann and E. Arnold, ch. 16.1.
Dordrecht: Kluwer Academic Publishers.
_atom_sites_solution_hydrogens
CIF
Codes which identify the methods used to locate the initial
atom sites. The *_primary code identifies how the first atom sites were determined; the *_secondary code identifies how the remaining non-hydrogen sites were located; and the *_hydrogens code identifies how the hydrogen sites were located.
Ref: Sheldrick, G. M., Hauptman, H. A., Weeks, C. M.,
Miller, R. and Usón, I. (2001). Ab initio phasing.
In International Tables for Crystallography,
Vol. F. Crystallography of biological macromolecules,
edited by M. G. Rossmann and E. Arnold, ch. 16.1.
Dordrecht: Kluwer Academic Publishers.
_atom_sites_special_details
CIF
Additional information about the atomic coordinates not coded
elsewhere in the CIF.
_ATOM_TYPE_[]
CIF
Data items in the ATOM_TYPE category record details about
properties of the atoms that occupy the atom sites, such as the atomic scattering factors.
Example:
loop_
_atom_type_symbol
_atom_type_oxidation_number
_atom_type_number_in_cell
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C 0 72 .017 .009 International_Tables_Vol_IV_Table_2.2B
H 0 100 0 0 International_Tables_Vol_IV_Table_2.2B
O 0 12 .047 .032 International_Tables_Vol_IV_Table_2.2B
N 0 4 .029 .018 International_Tables_Vol_IV_Table_2.2B
_atom_type_analytical_mass_%
CIF
Mass percentage of this atom type derived from chemical analysis.
_atom_type_description
CIF
A description of the atom(s) designated by this atom type. In
most cases, this will be the element name and oxidation state of a single atom species. For disordered or nonstoichiometric structures it will describe a combination of atom species.
Examples:
deuterium
0.34Fe+0.66Ni
_atom_type_number_in_cell
CIF
Total number of atoms of this atom type in the unit cell.
_atom_type_oxidation_number
CIF
Formal oxidation state of this atom type in the structure.
_atom_type_radius
CIF
Data names: _atom_type_radius_bond _atom_type_radius_contact
The effective intra- and intermolecular bonding radii in
angstroms of this atom type.
_atom_type_scat_Cromer_Mann
CIF
Data names: _atom_type_scat_Cromer_Mann_a1 _atom_type_scat_Cromer_Mann_a2 _atom_type_scat_Cromer_Mann_a3 _atom_type_scat_Cromer_Mann_a4 _atom_type_scat_Cromer_Mann_b1 _atom_type_scat_Cromer_Mann_b2 _atom_type_scat_Cromer_Mann_b3 _atom_type_scat_Cromer_Mann_b4 _atom_type_scat_Cromer_Mann_c
The Cromer-Mann scattering-factor coefficients used to calculate
the scattering factors for this atom type.
Ref: International Tables for X-ray Crystallography (1974).
Vol. IV, Table 2.2B
or International Tables for Crystallography (2004). Vol. C,
Tables 6.1.1.4 and 6.1.1.5
_atom_type_scat_dispersion
CIF
Data names: _atom_type_scat_dispersion_imag _atom_type_scat_dispersion_real
The imaginary and real components of the anomalous-dispersion
scattering factor, f'' and f', in electrons for this atom type
and the radiation given in _diffrn_radiation_wavelength.
_atom_type_scat_dispersion_source
CIF
Reference to source of real and imaginary dispersion
corrections for scattering factors used for this atom type.
Example:
International Tables Vol. IV Table 2.3.1
_atom_type_scat_length_neutron
CIF
The bound coherent scattering length in femtometres for the
atom type at the isotopic composition used for the diffraction experiment.
_atom_type_scat_source
CIF
Reference to source of scattering factors or scattering lengths
used for this atom type.
Example:
International Tables Vol. IV Table 2.4.6B
_atom_type_scat_versus_stol_list
CIF
A table of scattering factors as a function of sin theta over
lambda. This table should be well commented to indicate the items present. Regularly formatted lists are strongly recommended.
_atom_type_symbol
CIF
The code used to identify the atom species (singular or plural)
representing this atom type. Normally this code is the element symbol. The code may be composed of any character except an underscore with the additional proviso that digits designate an oxidation state and must be followed by a + or - character.
Examples:
C
Cu2+
H(SDS)
dummy
FeNi
_AUDIT_[]
CIF
Data items in the AUDIT category record details about the
creation and subsequent updating of the data block.
Example:
_audit_block_code TOZ_1991-03-20 _audit_block_doi 10.1107/S0108270191009630
_audit_creation_date 1991-03-20 _audit_creation_method from_xtal_archive_file_using_CIFIO _audit_update_record ; 1991-04-09 text and data added by Tony Willis. 1991-04-15 rec'd by co-editor as manuscript HL0007. 1991-04-17 adjustments based on first referee report. 1991-04-18 adjustments based on second referee report. ;
_audit_block_code
CIF
A code intended to identify uniquely the current data block.
Example:
TOZ_1991-03-20
_audit_block_doi
CIF
The digital object identifier (DOI) registered to identify
the data set publication represented by the current datablock. This can be used as a unique identifier for the datablock so long as the code used is a valid DOI (i.e. begins with a valid publisher prefix assigned by a Registration Agency and a suffix guaranteed to be unique by the publisher) and has had its metadata deposited with a DOI Registration Agency.
A DOI is a unique character string identifying any object of intellectual property. It provides a persistent identifier for an object on a digital network and permits the association of related current data in a structured extensible way. A DOI is an implementation of the Internet concepts of Uniform Resource Name and Universal Resource Locator managed according to the specifications of the International DOI Foundation (see http://www.doi.org).
Example:
10.5517/CC6V9DQ
_audit_creation_date
CIF
The date that the data block was created. The date format
is yyyy-mm-dd.
Example:
1990-07-12
_audit_creation_method
CIF
A description of how data were entered into the data block.
Example:
spawned by the program QBEE
_audit_update_record
CIF
A record of any changes to the data block. The update format
is a date (yyyy-mm-dd) followed by a description of the changes. The latest update entry is added to the bottom of this record.
Example:
1990-07-15 Updated by the Co-editor
_AUDIT_AUTHOR_[]
CIF
Data items in the AUDIT_AUTHOR category record details about
the author(s) of the data block.
Example:
loop_
_audit_author_name
_audit_author_address
'Fitzgerald, Paula M. D.'
; Department of Biophysical Chemistry
Merck Research Laboratories
PO Box 2000, Ry80M203
Rahway
New Jersey 07065
USA
;
'Van Middlesworth, J. F.'
; Department of Biophysical Chemistry
Merck Research Laboratories
PO Box 2000, Ry80M203
Rahway
New Jersey 07065
USA
;
_audit_author_address
CIF
The address of an author of this data block. If there are
multiple authors, _audit_author_address is looped with _audit_author_name.
Example:
Department
Institute
Street
City and postcode
COUNTRY
_audit_author_name
CIF
The name of an author of this data block. If there are multiple
authors, _audit_author_name is looped with _audit_author_address. The family name(s), followed by a comma and including any dynastic components, precedes the first name(s) or initial(s).
Examples:
Bleary, Percival R.
O'Neil, F.K.
Van den Bossche, G.
Yang, D.-L.
Simonov, Yu.A.
Müller, H.A.
Ross II, C.R.
_AUDIT_CONFORM_[]
CIF
Data items in the AUDIT_CONFORM category describe the
dictionary versions against which the data names appearing in the current data block are conformant.
Example:
_audit_conform_dict_name cif_core.dic _audit_conform_dict_version 2.4 _audit_conform_dict_location ftp://ftp.iucr.org/pub/cif_core.2.4.dic
_audit_conform_dict_location
CIF
A file name or uniform resource locator (URL) for the
dictionary to which the current data block conforms.
_audit_conform_dict_name
CIF
The string identifying the highest-level dictionary defining
data names used in this file.
_audit_conform_dict_version
CIF
The version number of the dictionary to which the
current data block conforms.
_AUDIT_CONTACT_AUTHOR_[]
CIF
Data items in the AUDIT_CONTACT_AUTHOR category record details
about the name and address of the author to be contacted concerning the contents of this data block.
Example:
loop_
_audit_contact_author_name
_audit_contact_author_address
_audit_contact_author_email
_audit_contact_author_fax
_audit_contact_author_phone
'Fitzgerald, Paula M. D.'
; Department of Biophysical Chemistry
Merck Research Laboratories
PO Box 2000, Ry80M203
Rahway
New Jersey 07065
USA
;
'[email protected]'
'1(908)5945510'
'1(908)5945510'
_audit_contact_author_address
CIF
The mailing address of the author of the data block to whom
correspondence should be addressed.
Example:
Department
Institute
Street
City and postcode
COUNTRY
_audit_contact_author_email
CIF
The electronic mail address of the author of the data block
to whom correspondence should be addressed, in a form recognizable to international networks. The format of e-mail addresses is given in Section 3.4, Address Specification, of Internet Message Format, RFC 2822, P. Resnick (Editor), Network Standards Group, April 2001.
Examples:
_audit_contact_author_fax
CIF
The facsimile telephone number of the author of the data
block to whom correspondence should be addressed.
The recommended style starts with the international dialing prefix, followed by the area code in parentheses, followed by the local number with no spaces.
Examples:
12(34)9477334
12()349477334
_audit_contact_author_name
CIF
The name of the author of the data block to whom correspondence
should be addressed.
The family name(s), followed by a comma and including any dynastic components, precedes the first name(s) or initial(s).
Examples:
Bleary, Percival R.
O'Neil, F.K.
Van den Bossche, G.
Yang, D.-L.
Simonov, Yu.A.
Müller, H.A.
Ross II, C.R.
_audit_contact_author_phone
CIF
The telephone number of the author of the data block to whom
correspondence should be addressed.
The recommended style starts with the international dialing prefix, followed by the area code in parentheses, followed by the local number and any extension number prefixed by 'x', with no spaces.
Examples:
12(34)9477330
12()349477330
12(34)9477330x5543
_AUDIT_LINK_[]
CIF
Data items in the AUDIT_LINK category record details about the
relationships between data blocks in the current CIF.
Examples:
loop_
_audit_link_block_code
_audit_link_block_description
. 'discursive text of paper with two structures'
morA_(1) 'structure 1 of 2'
morA_(2) 'structure 2 of 2'
loop_
_audit_link_block_code
_audit_link_block_description
. 'publication details'
KSE_COM 'experimental data common to ref./mod. structures'
KSE_REF 'reference structure'
KSE_MOD 'modulated structure'
_audit_link_block_code
CIF
The value of _audit_block_code associated with a data block
in the current file related to the current data block. The special value '.' may be used to refer to the current data block for completeness.
_audit_link_block_description
CIF
A textual description of the relationship of the referenced
data block to the current one.
_CELL_[]
CIF
Data items in the CELL category record details about the
crystallographic cell parameters and their measurement.
Example:
_cell_length_a 5.959(1) _cell_length_b 14.956(1) _cell_length_c 19.737(3) _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 1759.0(3)
_cell_measurement_temperature 293 _cell_measurement_reflns_used 25 _cell_measurement_theta_min 25 _cell_measurement_theta_max 31
_cell_angle
CIF
Data names: _cell_angle_alpha _cell_angle_beta _cell_angle_gamma
Unit-cell angles of the reported structure in degrees.
The values of _refln_index_h, *_k, *_l must correspond to the cell defined by these values and _cell_length_a, *_b and *_c. The values of _diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell transformation took place following the measurement of the diffraction intensities. See also _diffrn_reflns_transf_matrix_.
_cell_formula_units_Z
CIF
The number of the formula units in the unit cell as specified
by _chemical_formula_structural, _chemical_formula_moiety or _chemical_formula_sum.
_cell_length
CIF
Data names: _cell_length_a _cell_length_b _cell_length_c
Unit-cell lengths in angstroms corresponding to the structure
reported. The values of _refln_index_h, *_k, *_l must correspond to the cell defined by these values and _cell_angle_ values. The values of _diffrn_refln_index_h, *_k, *_l may not correspond to these values if a cell transformation took place following the measurement of the diffraction intensities. See also _diffrn_reflns_transf_matrix_.
_cell_measurement_pressure
CIF
The pressure in kilopascals at which the unit-cell parameters
were measured (not the pressure at which the sample was synthesized).
_cell_measurement_radiation
CIF
Description of the radiation used to measure the unit-cell data.
See also _cell_measurement_wavelength.
Examples:
neutron
Cu Kα
synchrotron
_cell_measurement_reflns_used
CIF
The total number of reflections used to determine the unit cell.
These reflections may be specified as _cell_measurement_refln_ data items.
_cell_measurement_temperature
CIF
The temperature in kelvins at which the unit-cell parameters
were measured (not the temperature of synthesis).
_cell_measurement_theta
CIF
Data names: _cell_measurement_theta_max _cell_measurement_theta_min
The maximum and minimum theta angles of reflections
used to measure the unit cell in degrees.
_cell_measurement_wavelength
CIF
The wavelength in angstroms of the radiation used to measure
the unit cell. If this is not specified, the wavelength is
assumed to be the same as that given in
_diffrn_radiation_wavelength.
_cell_reciprocal_angle
CIF
Data names: _cell_reciprocal_angle_alpha _cell_reciprocal_angle_beta _cell_reciprocal_angle_gamma
The angles defining the reciprocal cell in degrees. These
are related to those in the real cell by:
cos(recip-alpha)
= [cos(beta)*cos(gamma) - cos(alpha)]/[sin(beta)*sin(gamma)]
cos(recip-beta)
= [cos(gamma)*cos(alpha) - cos(beta)]/[sin(gamma)*sin(alpha)]
cos(recip-gamma)
= [cos(alpha)*cos(beta) - cos(gamma)]/[sin(alpha)*sin(beta)]
Ref: Buerger, M. J. (1942). X-ray Crystallography, p. 360.
New York: John Wiley & Sons Inc.
_cell_reciprocal_length
CIF
Data names: _cell_reciprocal_length_a _cell_reciprocal_length_b _cell_reciprocal_length_c
The reciprocal-cell lengths in inverse angstroms. These are
related to the real cell by:
recip-a = b*c*sin(alpha)/V
recip-b = c*a*sin(beta)/V
recip-c = a*b*sin(gamma)/V
where V is the cell volume.
Ref: Buerger, M. J. (1942). X-ray Crystallography, p. 360.
New York: John Wiley & Sons Inc.
_cell_special_details
CIF
A description of special aspects of the cell choice, noting
possible alternative settings.
Examples:
pseudo-orthorhombic
standard setting from 45 deg rotation around c
_cell_volume
CIF
Cell volume V in angstroms cubed.
V = a b c [1 - cos^2^(alpha) - cos^2^(beta) - cos^2^(gamma)
+ 2 cos(alpha) cos(beta) cos(gamma) ] ^1/2^
a = _cell_length_a b = _cell_length_b c = _cell_length_c alpha = _cell_angle_alpha beta = _cell_angle_beta gamma = _cell_angle_gamma
_CELL_MEASUREMENT_REFLN_[]
CIF
Data items in the CELL_MEASUREMENT_REFLN category record
details about the reflections used in the determination of the crystallographic cell parameters.
The _cell_measurement_refln_ data items would in general be used only for diffractometer measurements.
Example:
loop_
_cell_measurement_refln_index_h
_cell_measurement_refln_index_k
_cell_measurement_refln_index_l
_cell_measurement_refln_theta
-2 4 1 8.67
0 3 2 9.45
3 0 2 9.46
-3 4 1 8.93
-2 1 -2 7.53
10 0 0 23.77
0 10 0 23.78
-5 4 1 11.14
# - - - - data truncated for brevity - - - -
_cell_measurement_refln_index
CIF
Data names: _cell_measurement_refln_index_h _cell_measurement_refln_index_k _cell_measurement_refln_index_l
Miller indices of a reflection used for measurement of
the unit cell.
_cell_measurement_refln_theta
CIF
Theta angle in degrees for the reflection used for
measurement of the unit cell with the indices _cell_measurement_refln_index_.
_CHEMICAL_[]
CIF
Data items in the CHEMICAL category record details about the
composition and chemical properties of the compound. The formula data items must agree with those that specify the density, unit-cell and Z values.
Example:
_chemical_name_systematic
trans-bis(tricyclohexylphosphine)tetracarbonylmolybdenum(0)
_chemical_absolute_configuration
CIF
Necessary conditions for the assignment of
_chemical_absolute_configuration are given by H. D. Flack and
G. Bernardinelli (1999, 2000).
Ref: Flack, H. D. & Bernardinelli, G. (1999). Acta Cryst. A55,
908-915. (http://www.iucr.org/paper?sh0129)
Flack, H. D. & Bernardinelli, G. (2000). J. Appl. Cryst.
33, 1143-1148. (http://www.iucr.org/paper?ks0021)
_chemical_compound_source
CIF
Description of the source of the compound under study, or of the
parent molecule if a simple derivative is studied. This includes the place of discovery for minerals or the actual source of a natural product.
Examples:
From Norilsk (USSR)
Extracted from the bark of Cinchona Naturalis
_chemical_enantioexcess_bulk
CIF
The enantioexcess of the bulk material from which the
crystals were grown. A value of 0.0 indicates the racemate. A value of 1.0 indicates that the compound is enantiomerically pure.
Enantioexcess is defined in the IUPAC Recommendations (Moss et al., 1996). The composition of the crystal and bulk must be the same.
Ref: Moss G. P. et al. (1996). Basic Terminology of
Stereochemistry. Pure Appl. Chem., 68, 2193-2222.
http://www.chem.qmul.ac.uk/iupac/stereo/index.html
_chemical_enantioexcess_bulk_technique
CIF
The experimental technique used to determine the
enantioexcess of the bulk compound.
_chemical_enantioexcess_crystal
CIF
The enantioexcess of the crystal used for the diffraction
study. A value of 0.0 indicates the racemate. A value of 1.0 indicates that the crystal is enantiomerically pure.
Enantioexcess is defined in the IUPAC Recommendations (Moss et al., 1996).
Ref: Moss G. P. et al. (1996). Basic Terminology of
Stereochemistry. Pure Appl. Chem., 68, 2193-2222.
http://www.chem.qmul.ac.uk/iupac/stereo/index.html
_chemical_enantioexcess_crystal_technique
CIF
The experimental technique used to determine the
enantioexcess of the crystal.
_chemical_identifier_inchi
CIF
The IUPAC International Chemical Identifier (InChI) is
a textual identifier for chemical substances, designed to provide a standard and human-readable way to encode molecular information and to facilitate the search for such information in databases and on the web.
Ref: McNaught, A. (2006). Chem. Int. (IUPAC), 28 (6), 12-14.
http://www.iupac.org/inchi/
Example:
InChI=1/C10H8/c1-2-6-10-8-4-3-7-9(10)5-1/h1-8H
_chemical_identifier_inchi_key
CIF
The InChIKey is a compact hashed version of the full InChI
(IUPAC International Chemical Identifier), designed to allow for easy web searches of chemical compounds. See http://www.iupac.org/inchi/
Example:
InChIKey=OROGSEYTTFOCAN-DNJOTXNNBG
_chemical_identifier_inchi_version
CIF
The version number of the InChI standard to which the
associated chemical identifier string applies.
Example:
1.03
_chemical_melting_point
CIF
The temperature in kelvins at which the crystalline solid changes
to a liquid.
_chemical_melting_point
CIF
Data names: _chemical_melting_point_gt _chemical_melting_point_lt
A temperature in kelvins below which (*_lt) or above
which (*_gt) the melting point (the temperature at which the crystalline solid changes to a liquid) lies. These items allow a range of temperatures to be given.
_chemical_melting_point should always be used in preference
to these items whenever possible.
_chemical_name_common
CIF
Trivial name by which the compound is commonly known.
Example:
1-bromoestradiol
_chemical_name_mineral
CIF
Mineral name accepted by the International Mineralogical
Association. Use only for natural minerals. See also
_chemical_compound_source.
Example:
chalcopyrite
_chemical_name_structure_type
CIF
Commonly used structure-type name. Usually only applied to
minerals or inorganic compounds.
Examples:
perovskite
sphalerite
A15
_chemical_name_systematic
CIF
IUPAC or Chemical Abstracts full name of the compound.
Example:
1-bromoestra-1,3,5(10)-triene-3,17β-diol
_chemical_optical_rotation
CIF
The optical rotation in solution of the compound is
specified in the following format:
'[α]^TEMP^~WAVE~ = SORT (c = CONC, SOLV)'
where:
TEMP is the temperature of the measurement in degrees
Celsius,
WAVE is an indication of the wavelength of the light
used for the measurement,
CONC is the concentration of the solution given as the
mass of the substance in g per 100 ml of solution,
SORT is the signed value (preceded by a + or a - sign)
of 100.α/(l.c), where α is the signed optical
rotation in degrees measured in a cell of length l in
dm and c is the value of CONC as defined above, and
SOLV is the chemical formula of the solvent.
Example:
[α]^25^~D~ = +108 (c = 3.42, CHCl~3~)
_chemical_properties_biological
CIF
A free-text description of the biological properties of the
material.
Examples:
diverse biological activities including use as a
laxative and strong antibacterial activity against
S. aureus and weak activity against
cyclooxygenase-1 (COX-1)
antibiotic activity against Bacillus subtilis
(ATCC 6051) but no significant activity against
Candida albicans (ATCC 14053), Aspergillus flavus
(NRRL 6541) and Fusarium verticillioides (NRRL
25457)
weakly potent lipoxygenase nonredox inhibitor
no influenza A virus sialidase inhibitory and
plaque reduction activities
low toxicity against Drosophila melanogaster
_chemical_properties_physical
CIF
A free-text description of the physical properties of the
material.
Examples:
air-sensitive
moisture-sensitive
hygroscopic
deliquescent
oxygen-sensitive
photo-sensitive
pyrophoric
semiconductor
ferromagnetic at low temperature
paramagnetic and thermochromic
_chemical_temperature_decomposition
CIF
The temperature in kelvins at which the solid decomposes.
Example:
350
_chemical_temperature_decomposition
CIF
Data names: _chemical_temperature_decomposition_gt _chemical_temperature_decomposition_lt
A temperature in kelvins below which (*_lt) or above which
(*_gt) the solid is known to decompose. These items allow a range of temperatures to be given.
_chemical_temperature_decomposition should always be used in
preference to these items whenever possible.
Example:
350
_chemical_temperature_sublimation
CIF
The temperature in kelvins at which the solid sublimes.
Example:
350
_chemical_temperature_sublimation
CIF
Data names: _chemical_temperature_sublimation_gt _chemical_temperature_sublimation_lt
A temperature in kelvins below which (*_lt) or above which
(*_gt) the solid is known to sublime. These items allow a range of temperatures to be given.
_chemical_temperature_sublimation should always be used in
preference to these items whenever possible.
Example:
350
_CHEMICAL_CONN_ATOM_[]
CIF
Data items in the _chemical_conn_atom_ and _chemical_conn_bond_
categories record details about the two-dimensional (2D) chemical structure of the molecular species. They allow a 2D chemical diagram to be reconstructed for use in a publication or in a database search for structural and substructural relationships.
The _chemical_conn_atom_ data items provide information about the chemical properties of the atoms in the structure. In cases where crystallographic and molecular symmetry elements coincide, they must also contain symmetry-generated atoms, so that the _chemical_conn_atom_ and _chemical_conn_bond_ data items will always describe a complete chemical entity.
Example:
loop_
_chemical_conn_atom_number
_chemical_conn_atom_type_symbol
_chemical_conn_atom_display_x
_chemical_conn_atom_display_y
_chemical_conn_atom_NCA
_chemical_conn_atom_NH
1 S .39 .81 1 0
2 S .39 .96 2 0
3 N .14 .88 3 0
4 C .33 .88 3 0
5 C .11 .96 2 2
6 C .03 .96 2 2
7 C .03 .80 2 2
8 C .11 .80 2 2
9 S .54 .81 1 0
10 S .54 .96 2 0
11 N .80 .88 3 0
12 C .60 .88 3 0
13 C .84 .96 2 2
14 C .91 .96 2 2
15 C .91 .80 2 2
16 C .84 .80 2 2
_chemical_conn_atom_charge
CIF
The net integer charge assigned to this atom. This is the formal charge assignment normally found in chemical diagrams.
Examples:
1
-1
_chemical_conn_atom_display
CIF
Data names: _chemical_conn_atom_display_x _chemical_conn_atom_display_y
The 2D Cartesian coordinates (x,y) of the position of this atom
in a recognizable chemical diagram. The coordinate origin is at the lower left corner, the x axis is horizontal and the y axis is vertical. The coordinates must lie in the range 0.0 to 1.0. These coordinates can be obtained from projections of a suitable uncluttered view of the molecular structure.
_chemical_conn_atom_NCA
CIF
The number of connected atoms excluding terminal hydrogen atoms.
_chemical_conn_atom_NH
CIF
The total number of hydrogen atoms attached to this atom,
regardless of whether they are included in the refinement or
the _atom_site_ list. This number will be the same as
_atom_site_attached_hydrogens only if none of the hydrogen
atoms appear in the _atom_site_ list.
_chemical_conn_atom_number
CIF
The chemical sequence number to be associated with this atom.
_chemical_conn_atom_type_symbol
CIF
A code identifying the atom type. This code must match an
_atom_type_symbol code in the _atom_type_ list or be a
recognizable element symbol.
_CHEMICAL_CONN_BOND_[]
CIF
Data items in the _chemical_conn_atom_ and _chemical_conn_bond_
categories record details about the two-dimensional (2D) chemical structure of the molecular species. They allow a 2D chemical diagram to be reconstructed for use in a publication or in a database search for structural and substructural relationships.
The _chemical_conn_bond_ data items specify the connections between the atoms in the _chemical_conn_atom_ list and the nature of the chemical bond between these atoms.
Example:
loop_
_chemical_conn_bond_atom_1
_chemical_conn_bond_atom_2
_chemical_conn_bond_type
4 1 doub 4 3 sing
4 2 sing 5 3 sing
6 5 sing 7 6 sing
8 7 sing 8 3 sing
10 2 sing 12 9 doub
12 11 sing 12 10 sing
13 11 sing 14 13 sing
15 14 sing 16 15 sing
16 11 sing 17 5 sing
18 5 sing 19 6 sing
20 6 sing 21 7 sing
22 7 sing 23 8 sing
24 8 sing 25 13 sing
26 13 sing 27 14 sing
28 14 sing 29 15 sing
30 15 sing 31 16 sing
32 16 sing
_chemical_conn_bond_atom
CIF
Data names: _chemical_conn_bond_atom_1 _chemical_conn_bond_atom_2
Atom numbers which must match with chemical sequence numbers
specified as _chemical_conn_atom_number values. These link the
bond connection to the chemical numbering and atom sites.
_chemical_conn_bond_type
CIF
The chemical bond type associated with the connection between
the two sites _chemical_conn_bond_atom_1 and *_2.
_CHEMICAL_FORMULA_[]
CIF
_chemical_formula_ items specify the composition and chemical properties of the compound. The formula data items must agree with those that specify the density, unit-cell and Z values.
The following rules apply to the construction of the data items _chemical_formula_analytical, *_structural and *_sum. For the data item *_moiety, the formula construction is broken up into residues or moieties, i.e. groups of atoms that form a molecular unit or molecular ion. The rules given below apply within each moiety but different requirements apply to the way that moieties are connected (see _chemical_formula_moiety).
(1) Only recognized element symbols may be used.
(2) Each element symbol is followed by a 'count' number. A
count of '1' may be omitted.
(3) A space or parenthesis must separate each cluster of (element symbol + count).
(4) Where a group of elements is enclosed in parentheses, the multiplier for the group must follow the closing parenthesis. That is, all element and group multipliers are assumed to be printed as subscripted numbers. (An exception to this rule exists for *_moiety formulae where pre- and post-multipliers are permitted for molecular units.)
(5) Unless the elements are ordered in a manner that corresponds to their chemical structure, as in _chemical_formula_structural, the order of the elements within any group or moiety depends on whether carbon is present or not. If carbon is present, the order should be: C, then H, then the other elements in alphabetical order of their symbol. If carbon is not present, the elements are listed purely in alphabetical order of their symbol. This is the 'Hill' system used by Chemical Abstracts. This ordering is used in _chemical_formula_moiety and _chemical_formula_sum.
Examples:
_chemical_formula_moiety 'C18 H25 N O3' _chemical_formula_sum 'C18 H25 N O3' _chemical_formula_weight 303.40
_chemical_formula_iupac '[Mo (C O)4 (C18 H33 P)2]' _chemical_formula_moiety 'C40 H66 Mo O4 P2' _chemical_formula_structural '((C O)4 (P (C6 H11)3)2)Mo' _chemical_formula_sum 'C40 H66 Mo O4 P2' _chemical_formula_weight 768.81
_chemical_formula_analytical
CIF
Formula determined by standard chemical analysis including trace
elements. See the _chemical_formula_[] category description for
rules for writing chemical formulae. Parentheses are used only
for standard uncertainties (e.s.d.'s).
Example:
Fe2.45(2) Ni1.60(3) S4
_chemical_formula_iupac
CIF
Formula expressed in conformance with IUPAC rules for inorganic
and metal-organic compounds where these conflict with the rules for any other _chemical_formula_ entries. Typically used for formatting a formula in accordance with journal rules. This should appear in the data block in addition to the most appropriate of the other _chemical_formula_ data names.
Ref: IUPAC (1990). Nomenclature of Inorganic Chemistry.
Oxford: Blackwell Scientific Publications.
Example:
[Co Re (C12 H22 P)2 (C O)6].0.5C H3 O H
_chemical_formula_moiety
CIF
Formula with each discrete bonded residue or ion shown as a
separate moiety. See the _chemical_formula_[] category description for rules for writing chemical formulae. In addition to the general formulae requirements, the following rules apply: (1) Moieties are separated by commas ','. (2) The order of elements within a moiety follows general rule (5) in the _chemical_formula_[] category description. (3) Parentheses are not used within moieties but may surround a moiety. Parentheses may not be nested. (4) Charges should be placed at the end of the moiety. The charge '+' or '-' may be preceded by a numerical multiplier and should be separated from the last (element symbol + count) by a space. Pre- or post-multipliers may be used for individual moieties.
Examples:
C7 H4 Cl Hg N O3 S
C12 H17 N4 O S 1+, C6 H2 N3 O7 1-
C12 H16 N2 O6, 5(H2 O1)
(Cd 2+)3, (C6 N6 Cr 3-)2, 2(H2 O)
_chemical_formula_structural
CIF
See the _chemical_formula_[] category description for the rules
for writing chemical formulae for inorganics, organometallics,
metal complexes etc., in which bonded groups are preserved
as discrete entities within parentheses, with post-multipliers
as required. The order of the elements should give as much
information as possible about the chemical structure.
Parentheses may be used and nested as required. This formula
should correspond to the structure as actually reported,
i.e. trace elements not included in atom-type and atom-site
lists should not be included in this formula (see also
_chemical_formula_analytical).
Examples:
Ca ((Cl O3)2 O)2 (H2 O)6
(Pt (N H3)2 (C5 H7 N3 O)2) (Cl O4)2
_chemical_formula_sum
CIF
See the _chemical_formula_[] category description for the rules
for writing chemical formulae in which all discrete bonded
residues and ions are summed over the constituent elements,
following the ordering given in general rule (5) in the
_chemical_formula_[] category description. Parentheses are not
normally used.
Example:
C18 H19 N7 O8 S
_chemical_formula_weight
CIF
Formula mass in daltons. This mass should correspond to the
formulae given under _chemical_formula_structural, *_iupac, *_moiety or *_sum and, together with the Z value and cell parameters, should yield the density given as _exptl_crystal_density_diffrn.
_chemical_formula_weight_meas
CIF
Formula mass in daltons measured by a non-diffraction experiment.
_CITATION_[]
CIF
Data items in the CITATION category record details about the
literature cited as being relevant to the contents of the data block.
Example:
loop_
_citation_id
_citation_coordinate_linkage
_citation_title
_citation_country
_citation_page_first
_citation_page_last
_citation_year
_citation_journal_abbrev
_citation_journal_volume
_citation_journal_issue
_citation_journal_id_ASTM
_citation_journal_id_ISSN
_citation_book_title
_citation_book_publisher
_citation_book_id_ISBN
_citation_special_details
primary yes
; Crystallographic analysis of a complex between human
immunodeficiency virus type 1 protease and
acetyl-pepstatin at 2.0-Angstroms resolution.
;
US 14209 14219 1990 'J. Biol. Chem.' 265 .
HBCHA3 0021-9258 . . .
; The publication that directly relates to this coordinate
set.
;
2 no
; Three-dimensional structure of aspartyl-protease from
human immunodeficiency virus HIV-1.
;
UK 615 619 1989 'Nature' 337 .
NATUAS 0028-0836 . . .
; Determination of the structure of the unliganded enzyme.
;
3 no
; Crystallization of the aspartylprotease from human
immunodeficiency virus, HIV-1.
;
US 1919 1921 1989 'J. Biol. Chem.' 264 .
HBCHA3 0021-9258 . . .
; Crystallization of the unliganded enzyme.
;
_citation_abstract
CIF
Abstract for the citation. This is used most when the
citation is extracted from a bibliographic database that contains full text or abstract information.
_citation_abstract_id_CAS
CIF
The Chemical Abstracts Service (CAS) abstract identifier;
relevant for journal articles.
_citation_book_id_ISBN
CIF
The International Standard Book Number (ISBN) code assigned to
the book cited; relevant for books or book chapters.
_citation_book_publisher
CIF
The name of the publisher of the citation; relevant
for books or book chapters.
Example:
John Wiley
_citation_book_publisher_city
CIF
The location of the publisher of the citation; relevant
for books or book chapters.
Example:
New York
_citation_book_title
CIF
The title of the book in which the citation appeared; relevant
for books or book chapters.
_citation_coordinate_linkage
CIF
_citation_coordinate_linkage states whether or not this citation
is concerned with precisely the set of coordinates given in the data block. If, for instance, the publication described the same structure, but the coordinates had undergone further refinement prior to creation of the data block, the value of this data item would be 'no'.
_citation_country
CIF
The country of publication; relevant for books and book
chapters.
_citation_database_id_CSD
CIF
Identifier ('refcode') of the database record in the Cambridge
Structural Database that contains details of the cited structure.
Example:
LEKKUH
_citation_database_id_Medline
CIF
Accession number used by Medline to categorize a specific
bibliographic entry.
Example:
89064067
_citation_doi
CIF
The Digital Object Identifier (DOI) of the cited work.
A DOI is a unique character string identifying any object of intellectual property. It provides a persistent identifier for an object on a digital network and permits the association of related current data in a structured extensible way. A DOI is an implementation of the Internet concepts of Uniform Resource Name and Universal Resource Locator managed according to the specifications of the International DOI Foundation (see http://www.doi.org).
Example:
10.5517/CC6V9DQ
_citation_id
CIF
The value of _citation_id must uniquely identify a record in the
_citation_ list.
The _citation_id 'primary' should be used to indicate the
citation that the author(s) consider to be the most pertinent to
the contents of the data block.
Note that this item need not be a number; it can be any unique identifier.
Examples:
primary
1
2
3
_citation_journal_abbrev
CIF
Abbreviated name of the journal cited as given in the Chemical
Abstracts Service Source Index.
Example:
J. Mol. Biol.
_citation_journal_full
CIF
Full name of the journal cited; relevant for journal articles.
Example:
Journal of Molecular Biology
_citation_journal_id_ASTM
CIF
The American Society for Testing and Materials (ASTM) code
assigned to the journal cited (also referred to as the CODEN designator of the Chemical Abstracts Service); relevant for journal articles.
_citation_journal_id_CSD
CIF
The Cambridge Structural Database (CSD) code assigned to the
journal cited; relevant for journal articles. This is also the system used at the Protein Data Bank (PDB).
Example:
0070
_citation_journal_id_ISSN
CIF
The International Standard Serial Number (ISSN) code assigned to
the journal cited; relevant for journal articles.
_citation_journal_issue
CIF
Issue number of the journal cited; relevant for journal
articles.
Example:
2
_citation_journal_volume
CIF
Volume number of the journal cited; relevant for journal
articles.
Example:
174
_citation_language
CIF
Language in which the cited article is written.
Example:
German
_citation_page
CIF
Data names: _citation_page_first _citation_page_last
The first and last pages of the citation; relevant for
journal articles, books and book chapters.
_citation_publisher
CIF
The name of the publisher of the cited work. This
should be used for citations of journal articles or
datasets (in the latter case the publisher could be a
curated database). For books or book chapters use
_citation_book_publisher.
Example:
Cambridge Crystallographic Data Centre
_citation_special_details
CIF
A description of special aspects of the relationship
of the contents of the data block to the literature item cited.
Examples:
citation relates to this precise coordinate set
citation relates to earlier low-resolution structure
citation relates to further refinement of structure
reported in citation 2
_citation_title
CIF
The title of the citation; relevant for journal articles, books
and book chapters.
Example:
Structure of diferric duck ovotransferrin at 2.35 Å
resolution.
_citation_year
CIF
The year of the citation; relevant for journal articles, books
and book chapters.
Example:
1984
_CITATION_AUTHOR_[]
CIF
Data items in the CITATION_AUTHOR category record details
about the authors associated with the citations in the _citation_ list.
Example:
loop_
_citation_author_citation_id
_citation_author_name
primary 'Fitzgerald, P.M.D.'
primary 'McKeever, B.M.'
primary 'Van Middlesworth, J.F.'
primary 'Springer, J.P.'
primary 'Heimbach, J.C.'
primary 'Leu, C.-T.'
primary 'Herber, W.K.'
primary 'Dixon, R.A.F.'
primary 'Darke, P.L.'
2 'Navia, M.A.'
2 'Fitzgerald, P.M.D.'
2 'McKeever, B.M.'
2 'Leu, C.-T.'
2 'Heimbach, J.C.'
2 'Herber, W.K.'
2 'Sigal, I.S.'
2 'Darke, P.L.'
2 'Springer, J.P.'
3 'McKeever, B.M.'
3 'Navia, M.A.'
3 'Fitzgerald, P.M.D.'
3 'Springer, J.P.'
3 'Leu, C.-T.'
3 'Heimbach, J.C.'
3 'Herber, W.K.'
3 'Sigal, I.S.'
3 'Darke, P.L.'
_citation_author_citation_id
CIF
The value of _citation_author_citation_id must match an
identifier specified by _citation_id in the _citation_ list.
_citation_author_name
CIF
Name of an author of the citation; relevant for journal
articles, books and book chapters.
The family name(s), followed by a comma and including any dynastic components, precedes the first name(s) or initial(s).
Examples:
Bleary, Percival R.
O'Neil, F.K.
Van den Bossche, G.
Yang, D.-L.
Simonov, Yu.A.
Müller, H.A.
Ross II, C.R.
_citation_author_ordinal
CIF
This data name defines the order of the author's name in the
list of authors of a citation.
_CITATION_EDITOR_[]
CIF
Data items in the CITATION_EDITOR category record details
about the editor associated with the book or book chapter citations in the _citation_ list.
Example:
loop_
_citation_editor_citation_id
_citation_editor_name
5 'McKeever, B.M.'
5 'Navia, M.A.'
5 'Fitzgerald, P.M.D.'
5 'Springer, J.P.'
_citation_editor_citation_id
CIF
The value of _citation_editor_citation_id must match an
identifier specified by _citation_id in the _citation_ list.
_citation_editor_name
CIF
Name of an editor of the citation; relevant for books and
book chapters.
The family name(s), followed by a comma and including any dynastic components, precedes the first name(s) or initial(s).
Examples:
Bleary, Percival R.
O'Neil, F.K.
Van den Bossche, G.
Yang, D.-L.
Simonov, Yu.A.
Müller, H.A.
Ross II, C.R.
_citation_editor_ordinal
CIF
This data name defines the order of the editor's name in the
list of editors of a citation.
_COMPUTING_[]
CIF
Data items in the COMPUTING category record details about the
computer programs used in the crystal structure analysis.
Example:
_computing_data_collection 'CAD-4 (Enraf-Nonius, 1989)' _computing_cell_refinement 'CAD-4 (Enraf-Nonius, 1989)' _computing_data_reduction 'CFEO (Solans, 1978)' _computing_structure_solution 'SHELXS86 (Sheldrick, 1990)' _computing_structure_refinement 'SHELXL93 (Sheldrick, 1993)' _computing_molecular_graphics 'ORTEPII (Johnson, 1976)' _computing_publication_material 'PARST (Nardelli, 1983)'
_computing
CIF
Data names: _computing_cell_refinement _computing_data_collection _computing_data_reduction _computing_molecular_graphics _computing_publication_material _computing_structure_refinement _computing_structure_solution
Software used in the processing of the data. Give the program
or package name and a brief reference.
Examples:
CAD-4 (Enraf-Nonius, 1989)
DIFDAT, SORTRF, ADDREF (Hall & Stewart, 1990)
FRODO (Jones, 1986), ORTEP (Johnson, 1965)
CRYSTALS (Watkin, 1988)
SHELX85 (Sheldrick, 1985)
_DATABASE_[]
CIF
Data items in the DATABASE category record details about the
database identifiers of the data block.
These data items are assigned by database managers and should only appear in a CIF if they originate from that source.
Example:
_database_code_CSD 'VOBYUG'
_database_code
CIF
Data names: _database_code_CAS _database_code_COD _database_code_CSD _database_code_ICSD _database_code_MDF _database_code_NBS _database_code_PDB _database_code_PDF
The codes are assigned by databases: Chemical Abstracts;
Crystallography Open Database (COD); Cambridge Structural Database (organic and metal-organic compounds); Inorganic Crystal Structure Database; Metals Data File (metal structures); NBS (NIST) Crystal Data Database (lattice parameters); Protein Data Bank; and the Powder Diffraction File (JCPDS/ICDD).
_database_code_depnum_ccdc_archive
CIF
Deposition numbers assigned by the Cambridge Crystallographic
Data Centre (CCDC) to files containing structural information archived by the CCDC.
_database_code_depnum_ccdc_fiz
CIF
Deposition numbers assigned by the Fachinformationszentrum
Karlsruhe (FIZ) to files containing structural information archived by the Cambridge Crystallographic Data Centre (CCDC).
_database_code_depnum_ccdc_journal
CIF
Deposition numbers assigned by various journals to files
containing structural information archived by the Cambridge Crystallographic Data Centre (CCDC).
_database_CSD_history
CIF
A history of changes made by the Cambridge Crystallographic Data
Centre and incorporated into the Cambridge Structural Database (CSD).
_database_dataset_doi
CIF
The digital object identifier (DOI) registered to identify
a data set publication associated with the structure described in the current datablock. This should be used for a dataset obtained from a curated database such as CSD or PDB.
A DOI is a unique character string identifying any object of intellectual property. It provides a persistent identifier for an object on a digital network and permits the association of related current data in a structured extensible way. A DOI is an implementation of the Internet concepts of Uniform Resource Name and Universal Resource Locator managed according to the specifications of the International DOI Foundation (see http://www.doi.org).
Example:
10.2210/pdb4hhb/pdb
_database_journal
CIF
Data names: _database_journal_ASTM _database_journal_CSD
The ASTM CODEN designator for a journal as given in the
Chemical Source List maintained by the Chemical Abstracts Service, and the journal code used in the Cambridge Structural Database.
_DIFFRN_[]
CIF
Data items in the DIFFRN category record details about the
intensity measurements.
Example:
_diffrn_special_details
; θ scan width (1.0 + 0.14tanθ)°, θ scan rate
1.2° min^-1^. Background counts for 5 s on each side
every scan.
;
_diffrn_ambient_temperature 293
_diffrn_ambient_environment
CIF
The gas or liquid surrounding the sample, if not air.
Examples:
He
vacuum
mother liquor
_diffrn_ambient_pressure
CIF
The mean hydrostatic pressure in kilopascals at which the
intensities were measured.
_diffrn_ambient_pressure
CIF
Data names: _diffrn_ambient_pressure_gt _diffrn_ambient_pressure_lt
The mean hydrostatic pressure in kilopascals above which (*_gt)
or below which (*_lt) the intensities were measured. These items allow for a pressure range to be given.
_diffrn_ambient_pressure should always be used in
preference to these items whenever possible.
_diffrn_ambient_temperature
CIF
The mean temperature in kelvins at which the intensities
were measured.
_diffrn_ambient_temperature
CIF
Data names: _diffrn_ambient_temperature_gt _diffrn_ambient_temperature_lt
The mean temperature in kelvins above which (*_gt) or below
which (*_lt) the intensities were measured. These items allow a range of temperatures to be given.
_diffrn_ambient_temperature should always be used in preference
to these items whenever possible.
_diffrn_crystal_treatment
CIF
Remarks about how the crystal was treated prior to the intensity
measurements. Particularly relevant when intensities were measured at low temperature.
Examples:
equilibrated in hutch for 24 hours
flash frozen in liquid nitrogen
slow cooled with direct air stream
_diffrn_measured_fraction_theta_full
CIF
Fraction of unique (symmetry-independent) reflections measured
out to _diffrn_reflns_theta_full.
_diffrn_measured_fraction_theta_max
CIF
Fraction of unique (symmetry-independent) reflections measured
out to _diffrn_reflns_theta_max.
_diffrn_special_details
CIF
Special details of the intensity-measurement process. Should
include information about source instability, crystal motion, degradation and so on.
Example:
The results may not be entirely reliable
as the measurement was made during a heat
wave when the air-conditioning had failed.
_diffrn_symmetry_description
CIF
Observed diffraction point symmetry, systematic absences and
possible space group(s) or superspace group(s) compatible with these.
_DIFFRN_ATTENUATOR_[]
CIF
Data items in the DIFFRN_ATTENUATOR category record details
about the diffraction attenuator scales employed.
Example:
loop_
_diffrn_attenuator_code
_diffrn_attenuator_scale
0 1.00
1 16.97
2 33.89
_diffrn_attenuator_code
CIF
A code associated with a particular attenuator setting. This code
is referenced by the _diffrn_refln_attenuator_code which is stored with the intensities. See _diffrn_attenuator_scale.
_diffrn_attenuator_material
CIF
Material from which the attenuator is made.
_diffrn_attenuator_scale
CIF
The scale factor applied when an intensity measurement is
reduced by an attenuator identified by _diffrn_attenuator_code.
The measured intensity must be multiplied by this scale to
convert it to the same scale as unattenuated intensities.
_DIFFRN_DETECTOR_[]
CIF
Data items in the DIFFRN_DETECTOR category describe the
detector used to measure the scattered radiation, including any analyser and post-sample collimation.
Example:
_diffrn_detector 'multiwire' _diffrn_detector_type 'Siemens'
_diffrn_detector
CIF
The general class of the radiation detector.
Examples:
photographic film
scintillation counter
CCD plate
BF~3~ counter
_diffrn_detector_area_resol_mean
CIF
The resolution of an area detector, in pixels/mm.
_diffrn_detector_details
CIF
A description of special aspects of the radiation detector.
_diffrn_detector_dtime
CIF
The deadtime in microseconds of the detector used to measure
the diffraction intensities.
_diffrn_detector_type
CIF
The make, model or name of the detector device used.
_diffrn_radiation_detector
CIF
The detector used to measure the diffraction intensities.
_diffrn_radiation_detector_dtime
CIF
The deadtime in microseconds of the detector used to measure
the diffraction intensities.
_DIFFRN_MEASUREMENT_[]
CIF
Data items in the DIFFRN_MEASUREMENT category refer to the
mounting of the sample and to the goniometer on which it is mounted.
Example:
_diffrn_measurement_device_type 'Philips PW1100/20 diffractometer' _diffrn_measurement_method θ/2θ
_diffrn_measurement_details
CIF
A description of special aspects of the intensity measurement.
Example:
440 frames of 0.25°
_diffrn_measurement_device
CIF
The general class of goniometer or device used to support
and orient the specimen.
Examples:
three-circle diffractometer
four-circle diffractometer
κ-geometry diffractometer
oscillation camera
precession camera
_diffrn_measurement_device_details
CIF
A description of special aspects of the device used to measure
the diffraction intensities.
Example:
commercial goniometer modified locally to
allow for 90° τ arc
_diffrn_measurement_device_type
CIF
The make, model or name of the measurement device
(goniometer) used.
_diffrn_measurement_method
CIF
Method used to measure the intensities.
Example:
profile data from θ/2θ scans
_diffrn_measurement_specimen_support
CIF
The physical device used to support the crystal during data
collection.
Examples:
glass capillary
quartz capillary
fiber
metal loop
_DIFFRN_ORIENT_MATRIX_[]
CIF
Data items in the DIFFRN_ORIENT_MATRIX category record details
about the orientation matrix used in the measurement of the diffraction intensities.
Example:
_diffrn_orient_matrix_UB_11 -0.04170 _diffrn_orient_matrix_UB_12 -0.01429 _diffrn_orient_matrix_UB_13 -0.02226 _diffrn_orient_matrix_UB_21 -0.00380 _diffrn_orient_matrix_UB_22 -0.05578 _diffrn_orient_matrix_UB_23 -0.05048 _diffrn_orient_matrix_UB_31 0.00587 _diffrn_orient_matrix_UB_32 -0.13766 _diffrn_orient_matrix_UB_33 0.02277
_diffrn_orient_matrix_type 'TEXSAN convention (MSC, 1989)'
_diffrn_orient_matrix_type
CIF
A description of the orientation matrix type and how it should
be applied to define the orientation of the crystal precisely with respect to the diffractometer axes.
_diffrn_orient_matrix_UB
CIF
Data names: _diffrn_orient_matrix_UB_11 _diffrn_orient_matrix_UB_12 _diffrn_orient_matrix_UB_13 _diffrn_orient_matrix_UB_21 _diffrn_orient_matrix_UB_22 _diffrn_orient_matrix_UB_23 _diffrn_orient_matrix_UB_31 _diffrn_orient_matrix_UB_32 _diffrn_orient_matrix_UB_33
The elements of the diffractometer orientation matrix. These
define the dimensions of the reciprocal cell and its orientation
to the local diffractometer axes. See _diffrn_orient_matrix_type.
_DIFFRN_ORIENT_REFLN_[]
CIF
Data items in the DIFFRN_ORIENT_REFLN category record details
about the reflections that define the orientation matrix used in the measurement of the diffraction intensities.
Example:
loop_
_diffrn_orient_refln_index_h
_diffrn_orient_refln_index_k
_diffrn_orient_refln_index_l
_diffrn_orient_refln_angle_theta
_diffrn_orient_refln_angle_phi
_diffrn_orient_refln_angle_omega
_diffrn_orient_refln_angle_kappa
-3 2 3 7.35 44.74 2.62 17.53
-4 1 0 9.26 83.27 8.06 5.79
0 0 6 5.85 -43.93 -25.36 86.20
2 1 3 7.36 -57.87 6.26 5.42
0 0 -6 5.85 -161.59 36.96 -86.79
-3 1 0 6.74 80.28 5.87 2.60
2 0 3 5.86 -76.86 -0.17 21.34
0 0 12 11.78 -44.02 -19.51 86.41
0 0 -12 11.78 -161.67 42.81 -86.61
-5 1 0 11.75 86.24 9.16 7.44
0 4 6 11.82 -19.82 10.45 4.19
5 0 6 14.13 -77.28 10.17 15.34
8 0 0 20.79 -77.08 25.30 -13.96
_diffrn_orient_refln_angle
CIF
Data names: _diffrn_orient_refln_angle_chi _diffrn_orient_refln_angle_kappa _diffrn_orient_refln_angle_omega _diffrn_orient_refln_angle_phi _diffrn_orient_refln_angle_psi _diffrn_orient_refln_angle_theta
Diffractometer angles of a reflection used to define
the orientation matrix in degrees. See
_diffrn_orient_matrix_UB_ and
_diffrn_orient_refln_index_h, *_k and *_l.
_diffrn_orient_refln_index
CIF
Data names: _diffrn_orient_refln_index_h _diffrn_orient_refln_index_k _diffrn_orient_refln_index_l
The indices of a reflection used to define the orientation
matrix. See _diffrn_orient_matrix_.
_DIFFRN_RADIATION_[]
CIF
Data items in the DIFFRN_RADIATION category describe the
radiation used in measuring the diffraction intensities, its collimation and monochromatization before the sample.
Post-sample treatment of the beam is described by data items in the DIFFRN_DETECTOR category.
Example:
_diffrn_radiation_type 'Cu Kα' _diffrn_radiation_monochromator 'graphite'
_diffrn_radiation_collimation
CIF
The collimation or focusing applied to the radiation.
Examples:
0.3 mm double-pinhole
0.5 mm
focusing mirrors
_diffrn_radiation_filter_edge
CIF
Absorption edge in angstroms of the radiation filter used.
_diffrn_radiation_inhomogeneity
CIF
Half-width in millimetres of the incident beam in the
direction perpendicular to the diffraction plane.
_diffrn_radiation_monochromator
CIF
The method used to obtain monochromatic radiation. If a mono-
chromator crystal is used, the material and the indices of the Bragg reflection are specified.
Examples:
Zr filter
Ge 220
none
equatorial mounted graphite
_diffrn_radiation_polarisn_norm
CIF
The angle in degrees, as viewed from the specimen, between the
perpendicular component of the polarization and the diffraction
plane. See _diffrn_radiation_polarisn_ratio.
_diffrn_radiation_polarisn_ratio
CIF
Polarization ratio of the diffraction beam incident on the
crystal. It is the ratio of the perpendicularly polarized to the
parallel polarized components of the radiation. The perpendicular
component forms an angle of _diffrn_radiation_polarisn_norm to
the normal to the diffraction plane of the sample (i.e. the plane
containing the incident and reflected beams).
_diffrn_radiation_probe
CIF
The nature of the radiation used (i.e. the name of the
subatomic particle or the region of the electromagnetic spectrum). It is strongly recommended that this information be given, so that the probe radiation can be simply determined.
_diffrn_radiation_type
CIF
The type of the radiation. This is used to give a more
detailed description than _diffrn_radiation_probe and is
typically a description of the X-ray wavelength in Siegbahn
notation.
Examples:
Cu Kα
Cu Kα~1~
Cu K-L~2,3~
white-beam
_diffrn_radiation_xray_symbol
CIF
The IUPAC symbol for the X-ray wavelength for the probe
radiation.
_DIFFRN_RADIATION_WAVELENGTH_[]
CIF
Data items in the DIFFRN_RADIATION_WAVELENGTH category describe
the wavelength of the radiation used in measuring the diffraction intensities. Items may be looped to identify and assign weights to distinct wavelength components from a polychromatic beam.
Example:
_diffrn_radiation_wavelength 1.5418
_diffrn_radiation_wavelength
CIF
The radiation wavelength in angstroms.
_diffrn_radiation_wavelength_details
CIF
Information about the determination of the radiation
wavelength that is not conveyed completely by an
enumerated value of _diffrn_radiation_wavelength_determination.
_diffrn_radiation_wavelength_determination
CIF
The method of determination of incident wavelength.
_diffrn_radiation_wavelength_id
CIF
An arbitrary code identifying each value of
_diffrn_radiation_wavelength. Items in the DIFFRN_RADIATION category are looped when multiple wavelengths are used. This code is used to link with the _diffrn_refln_ list. It must match with one of the _diffrn_refln_wavelength_id codes.
Examples:
x1
x2
neut
_diffrn_radiation_wavelength_wt
CIF
The relative weight of a wavelength identified by the code
_diffrn_radiation_wavelength_id in the list of wavelengths.
_DIFFRN_REFLN_[]
CIF
Data items in the DIFFRN_REFLN category record details about
the intensities measured in the diffraction experiment.
The DIFFRN_REFLN data items refer to individual intensity measurements and must be included in looped lists.
(The DIFFRN_REFLNS data items specify the parameters that apply to all intensity measurements. The DIFFRN_REFLNS data items are not looped.)
Example:
loop_
_diffrn_refln_index_h
_diffrn_refln_index_k
_diffrn_refln_index_l
_diffrn_refln_angle_chi
_diffrn_refln_scan_rate
_diffrn_refln_counts_bg_1
_diffrn_refln_counts_total
_diffrn_refln_counts_bg_2
_diffrn_refln_angle_theta
_diffrn_refln_angle_phi
_diffrn_refln_angle_omega
_diffrn_refln_angle_kappa
_diffrn_refln_scan_width
_diffrn_refln_elapsed_time
0 0 -16 0. 4.12 28 127 36 33.157 -75.846 16.404 50.170 1.516 19.43
0 0 -15 0. 4.12 38 143 28 30.847 -75.846 14.094 50.170 1.516 19.82
0 0 -14 0. 1.03 142 742 130 28.592 -75.846 11.839 50.170 1.516 21.32
0 0 -13 0. 4.12 26 120 37 26.384 -75.846 9.631 50.170 1.450 21.68
0 0 -12 0. 0.97 129 618 153 24.218 -75.846 7.464 50.170 1.450 23.20
0 0 -11 0. 4.12 33 107 38 22.087 -75.846 5.334 50.170 1.384 23.55
0 0 -10 0. 4.12 37 146 33 19.989 -75.846 3.235 50.170 1.384 23.90
0 0 -9 0. 4.12 50 179 49 17.918 -75.846 1.164 50.170 1.384 24.25
# - - - - data truncated for brevity - - - -
3 4 -4 0. 1.03 69 459 73 30.726 -53.744 46.543 -47.552 1.516 2082.58
3 4 -5 0. 1.03 91 465 75 31.407 -54.811 45.519 -42.705 1.516 2084.07
3 14 -6 0. 1.03 84 560 79 32.228 -55.841 44.745 -38.092 1.516 2085.57
# - - - - data truncated for brevity - - - -
_diffrn_refln_angle
CIF
Data names: _diffrn_refln_angle_chi _diffrn_refln_angle_kappa _diffrn_refln_angle_omega _diffrn_refln_angle_phi _diffrn_refln_angle_psi _diffrn_refln_angle_theta
The diffractometer angles of a reflection in degrees. These
correspond to the specified orientation matrix and the original measured cell before any subsequent cell transformations.
_diffrn_refln_attenuator_code
CIF
The code identifying the attenuator setting for this reflection.
This code must match one of the _diffrn_attenuator_code values.
_diffrn_refln_class_code
CIF
The code identifying the class to which this reflection has
been assigned. This code must match a value of
_diffrn_reflns_class_code. Reflections may be grouped into
classes for a variety of purposes. For example, for modulated
structures each reflection class may be defined by the
number m=sum|m~i~|, where the m~i~ are the integer coefficients
that, in addition to h,k,l, index the corresponding diffraction
vector in the basis defined for the reciprocal lattice.
_diffrn_refln_counts
CIF
Data names: _diffrn_refln_counts_bg_1 _diffrn_refln_counts_bg_2 _diffrn_refln_counts_net _diffrn_refln_counts_peak _diffrn_refln_counts_total
The diffractometer counts for the measurements: background
before the peak, background after the peak, net counts after background removed, counts for peak scan or position, and the total counts (background plus peak).
_diffrn_refln_crystal_id
CIF
Code identifying each crystal if multiple crystals are used. Is
used to link with _exptl_crystal_id in the _exptl_crystal_ list.
_diffrn_refln_detect_slit
CIF
Data names: _diffrn_refln_detect_slit_horiz _diffrn_refln_detect_slit_vert
Total slit apertures in degrees in the diffraction plane
(*_horiz) and perpendicular to the diffraction plane (*_vert).
_diffrn_refln_elapsed_time
CIF
Elapsed time in minutes from the start of the diffraction
experiment to the measurement of this intensity.
_diffrn_refln_index
CIF
Data names: _diffrn_refln_index_h _diffrn_refln_index_k _diffrn_refln_index_l
Miller indices of a measured reflection. These need not match
the _refln_index_h, *_k, *_l values if a transformation of the original measured cell has taken place. Details of the cell transformation are given in _diffrn_reflns_reduction_process. See also _diffrn_reflns_transf_matrix_.
_diffrn_refln_intensity_net
CIF
Net intensity calculated from the diffraction counts after
the attenuator and standard scales have been applied.
_diffrn_refln_intensity_sigma
CIF
Standard uncertainty (e.s.d.) of the net intensity calculated
from the diffraction counts after the attenuator and standard scales have been applied.
_diffrn_refln_intensity_u
CIF
Standard uncertainty of the net intensity calculated from
the diffraction counts after the attenuator and standard scales have been applied.
_diffrn_refln_scale_group_code
CIF
The code identifying the scale applicable to this reflection.
This code must match with a specified _diffrn_scale_group_code
value.
_diffrn_refln_scan_mode
CIF
The code identifying the mode of scanning for measurements
using a diffractometer. See _diffrn_refln_scan_width and _diffrn_refln_scan_mode_backgd.
_diffrn_refln_scan_mode_backgd
CIF
The code identifying the mode of scanning a reflection to measure
the background intensity.
_diffrn_refln_scan_rate
CIF
The rate of scanning a reflection in
degrees per minute to measure the intensity.
_diffrn_refln_scan_time_backgd
CIF
The time spent measuring each background in seconds.
_diffrn_refln_scan_width
CIF
The scan width in degrees of the scan mode defined by the code
_diffrn_refln_scan_mode.
_diffrn_refln_sint/lambda
CIF
The (sin theta)/lambda value in reciprocal angstroms for
this reflection.
_diffrn_refln_standard_code
CIF
A code indicating that this reflection was measured as a
standard reflection. The value must be '.' or match one of
the _diffrn_standard_refln_code values.
Examples:
1
2
3
s1
s2
s3
A
B
C
_diffrn_refln_wavelength
CIF
The mean wavelength in angstroms of the radiation used to measure
the intensity of this reflection. This is an important parameter for reflections measured using energy-dispersive detectors or the Laue method.
_diffrn_refln_wavelength_id
CIF
Code identifying the wavelength in the _diffrn_radiation_ list.
Examples:
x1
x2
neut
_DIFFRN_REFLNS_[]
CIF
Data items in the DIFFRN_REFLNS category record details about
the set of intensities measured in the diffraction experiment.
The DIFFRN_REFLNS data items specify the parameters that apply to all intensity measurements. The DIFFRN_REFLNS data items are not looped.
(The DIFFRN_REFLN data items refer to individual intensity measurements and must be included in looped lists.)
Example:
_diffrn_reflns_number 1592 _diffrn_reflns_av_R_equivalents 0 _diffrn_reflns_av_unetI/netI .027 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 6 _diffrn_reflns_limit_k_min -17 _diffrn_reflns_limit_k_max 0 _diffrn_reflns_limit_l_min 0 _diffrn_reflns_limit_l_max 22 _diffrn_reflns_theta_min 3.71 _diffrn_reflns_theta_max 61.97
_diffrn_reflns_av_R_equivalents
CIF
The residual [sum av|del(I)| / sum |av(I)|] for
symmetry-equivalent reflections used to calculate the average intensity av(I). The av|del(I)| term is the average absolute difference between av(I) and the individual symmetry-equivalent intensities.
_diffrn_reflns_av_sigmaI/netI
CIF
Measure [sum |u(net I)|/sum|net I|] for all measured reflections.
_diffrn_reflns_av_unetI/netI
CIF
Measure [sum |u(net I)|/sum|net I|] for all measured reflections.
_diffrn_reflns_Laue_measured_fraction_full
CIF
Fraction of Laue unique reflections (symmetry-independent in
the Laue group) measured out to the resolution given in _diffrn_reflns_resolution_full or _diffrn_reflns_theta_full. The Laue group always contains a centre of symmetry so that the reflection h,k,l is always equivalent to the reflection -h,-k,-l even in space groups without a centre of symmetry. This number should not be less than 0.95, since it represents the fraction of reflections measured in the part of the diffraction pattern that is essentially complete.
_diffrn_reflns_Laue_measured_fraction_max
CIF
Fraction of Laue unique reflections (symmetry-independent in
the Laue group) measured out to the resolution given in _diffrn_reflns_resolution_max or _diffrn_reflns_theta_max. The Laue group always contains a centre of symmetry so that the reflection h,k,l is always equivalent to the reflection -h,-k,-l even in space groups without a centre of symmetry.
_diffrn_reflns_limit
CIF
Data names: _diffrn_reflns_limit_h_max _diffrn_reflns_limit_h_min _diffrn_reflns_limit_k_max _diffrn_reflns_limit_k_min _diffrn_reflns_limit_l_max _diffrn_reflns_limit_l_min
The limits on the Miller indices of the intensities specified
by _diffrn_refln_index_h, *_k, *_l.
_diffrn_reflns_number
CIF
The total number of measured intensities, excluding
reflections that are classed as systematically absent arising from translational symmetry in the crystal unit cell.
_diffrn_reflns_point_group_measured_fraction_full
CIF
Fraction of crystal point-group unique reflections (i.e.
symmetry-independent in the crystal point group) measured out to the resolution given in _diffrn_reflns_resolution_full or _diffrn_reflns_theta_full. For space groups that do not contain a centre of symmetry the reflections h,k,l and -h,-k,-l are independent. This number should not be less than 0.95, since it represents the fraction of reflections measured in the part of the diffraction pattern that is essentially complete.
_diffrn_reflns_point_group_measured_fraction_max
CIF
Fraction of crystal point-group unique reflections (i.e.
symmetry-independent in the crystal point group) measured out to the resolution given in _diffrn_reflns_resolution_max or _diffrn_reflns_theta_max. For space groups that do not contain a centre of symmetry the reflections h,k,l and -h,-k,-l are independent.
_diffrn_reflns_reduction_process
CIF
A description of the process used to reduce the intensities
into structure-factor magnitudes.
Example:
data averaged using Fisher test
_diffrn_reflns_resolution_full
CIF
The resolution in reciprocal angstroms at which the measured
reflection count is close to complete. The fraction of unique
reflections measured out to this angle is given by
_diffrn_measured_fraction_theta_full.
_diffrn_reflns_resolution_max
CIF
Maximum resolution in reciprocal angstroms of the measured
diffraction pattern. The fraction of unique reflections
measured out to this angle is given by
_diffrn_measured_fraction_theta_max
_diffrn_reflns_theta_full
CIF
The theta angle (in degrees) at which the measured reflection
count is close to complete. The fraction of unique reflections
measured out to this angle is given by
_diffrn_measured_fraction_theta_full.
_diffrn_reflns_theta_max
CIF
Maximum theta angle in degrees for the measured intensities.
The fraction of unique reflections measured out to this angle
is given by _diffrn_measured_fraction_theta_max
_diffrn_reflns_theta_min
CIF
Minimum theta angle in degrees for the measured intensities.
_diffrn_reflns_transf_matrix
CIF
Data names: _diffrn_reflns_transf_matrix_11 _diffrn_reflns_transf_matrix_12 _diffrn_reflns_transf_matrix_13 _diffrn_reflns_transf_matrix_21 _diffrn_reflns_transf_matrix_22 _diffrn_reflns_transf_matrix_23 _diffrn_reflns_transf_matrix_31 _diffrn_reflns_transf_matrix_32 _diffrn_reflns_transf_matrix_33
Elements of the matrix used to transform the diffraction
reflection indices _diffrn_refln_index_h, *_k, *_l into the _refln_index_h, *_k, *_l indices. |11 12 13| (h k l) diffraction |21 22 23| = (h' k' l') |31 32 33|
_DIFFRN_REFLNS_CLASS_[]
CIF
Data items in the DIFFRN_REFLNS_CLASS category record details
about the classes of reflections measured in the diffraction experiment.
Example:
loop_
_diffrn_reflns_class_number
_diffrn_reflns_class_d_res_high
_diffrn_reflns_class_d_res_low
_diffrn_reflns_class_av_R_eq
_diffrn_reflns_class_code
_diffrn_reflns_class_description
1580 0.551 6.136 0.015 'Main'
'm=0; main reflections'
1045 0.551 6.136 0.010
'Sat1' 'm=1; first-order satellites'
_diffrn_reflns_class_av_R_eq
CIF
For each reflection class, the residual
[sum av|del(I)|/sum|av(I)|] for symmetry-equivalent reflections used to calculate the average intensity av(I). The av|del(I)| term is the average absolute difference between av(I) and the individual intensities.
_diffrn_reflns_class_av_sgI/I
CIF
Measure [sum|u(net I)|/sum|net I|] for all measured intensities
in a reflection class.
_diffrn_reflns_class_av_uI/I
CIF
Measure [sum|u(net I)|/sum|net I|] for all measured intensities
in a reflection class.
_diffrn_reflns_class_code
CIF
The code identifying a certain reflection class.
Examples:
1
m1
s2
_diffrn_reflns_class_d_res_high
CIF
The smallest value in angstroms of the interplanar
spacings of the reflections in each reflection class. This is called the highest resolution for this reflection class.
_diffrn_reflns_class_d_res_low
CIF
The highest value in angstroms of the interplanar
spacings of the reflections in each reflection class. This is called the lowest resolution for this reflection class.
_diffrn_reflns_class_description
CIF
Description of each reflection class.
Examples:
m=1 first order satellites
H0L0 common projection reflections
_diffrn_reflns_class_number
CIF
The total number of measured intensities for each reflection
class, excluding the systematic absences arising from centring translations.
_DIFFRN_SCALE_GROUP_[]
CIF
Data items in the DIFFRN_SCALE_GROUP category record details
of the scaling factors applied to place all intensities in the reflection lists on a common scale.
Scaling groups might, for instance, correspond to each film in a multi-film data set or each crystal in a multi-crystal data set.
Example:
loop_
_diffrn_scale_group_code
_diffrn_scale_group_I_net
1 .86473
2 1.0654
_diffrn_scale_group_code
CIF
The code identifying a specific measurement group (e.g. for
multi-film or multi-crystal data). The code must match a
_diffrn_refln_scale_group_code in the reflection list.
Examples:
1
2
3
s1
A
B
c1
c2
c3
_diffrn_scale_group_I_net
CIF
The scale for a specific measurement group which is to be
multiplied with the net intensity to place all intensities in the _diffrn_refln_ or _refln_ list on a common scale.
_DIFFRN_SOURCE_[]
CIF
Data items in the DIFFRN_SOURCE category record details of
the source of radiation used in the diffraction experiment.
Example:
_diffrn_source 'rotating anode X-ray tube' _diffrn_source_type 'Rigaku RU-200' _diffrn_source_power 50 _diffrn_source_current 180 _diffrn_source_size '8 mm x 0.4 mm broad focus'
_diffrn_radiation_source
CIF
The source of radiation.
_diffrn_source
CIF
The general class of the source of radiation.
Examples:
sealed X-ray tube
nuclear reactor
spallation source
electron microscope
rotating-anode X-ray tube
synchrotron
_diffrn_source_current
CIF
The current in milliamperes at which the radiation source was
operated.
_diffrn_source_details
CIF
A description of special aspects of the source.
_diffrn_source_power
CIF
The power in kilowatts at which the radiation source was
operated.
_diffrn_source_size
CIF
The dimensions of the source as viewed from the sample.
Examples:
8mm x 0.4 mm fine-focus
broad focus
_diffrn_source_take-off_angle
CIF
The complement of the angle in degrees between the normal
to the surface of the X-ray tube target and the primary X-ray beam for beams generated by traditional X-ray tubes.
Example:
1.53
_diffrn_source_target
CIF
The chemical element symbol for the X-ray target
(usually the anode) used to generate X-rays. This can also be used for spallation sources.
_diffrn_source_type
CIF
The make, model or name of the source of radiation.
Examples:
NSLS beamline X8C
Rigaku RU200
_diffrn_source_voltage
CIF
The voltage in kilovolts at which the radiation source was
operated.
_DIFFRN_STANDARD_REFLN_[]
CIF
Data items in the DIFFRN_STANDARD_REFLN category record details
about the reflections treated as standards during the measurement of the diffraction intensities.
Note that these are the individual standard reflections, not the results of the analysis of the standard reflections.
Example:
loop_
_diffrn_standard_refln_index_h
_diffrn_standard_refln_index_k
_diffrn_standard_refln_index_l
3 2 4 1 9 1 3 0 10
_diffrn_standard_refln_code
CIF
The code identifying a reflection measured as a standard
reflection with the indices _diffrn_standard_refln_index_.
This is the same code as the _diffrn_refln_standard_code in
the _diffrn_refln_ list.
Examples:
1
2
3
s1
A
B
_diffrn_standard_refln_index
CIF
Data names: _diffrn_standard_refln_index_h _diffrn_standard_refln_index_k _diffrn_standard_refln_index_l
Miller indices of standard reflections used in the diffraction
measurement process.
_DIFFRN_STANDARDS_[]
CIF
Data items in the DIFFRN_STANDARDS category record details
about the set of standard reflections used to monitor intensity stability during the measurement of diffraction intensities.
Note that these records describe properties common to the set of standard reflections, not the standard reflections themselves.
Example:
_diffrn_standards_number 3 _diffrn_standards_interval_time 120 _diffrn_standards_decay_% 0
_diffrn_standards_decay_%
CIF
The percentage decrease in the mean
intensity of the set of standard reflections measured at the start of the measurement process and at the finish. This value usually affords a measure of the overall decay in crystal quality during the diffraction measurement process. Negative values are used in exceptional instances where the final intensities are greater than the initial ones. If no measurable decay has occurred, the standard uncertainty should be quoted to indicate the maximum possible value the decay might have. A range of 3 standard uncertainties is considered possible. Thus 0.0(1) would indicate a decay of less than 0.3% or an enhancement of less than 0.3%.
Examples:
0.5(1)
-1(1)
0.0(2)
_diffrn_standards_interval
CIF
Data names: _diffrn_standards_interval_count _diffrn_standards_interval_time
The number of reflection intensities, or the time in minutes,
between the measurement of standard reflection intensities.
_diffrn_standards_number
CIF
The number of unique standard reflections used during the
measurement of the diffraction intensities.
_diffrn_standards_scale_sigma
CIF
The standard uncertainty (e.s.d.) of the individual mean
standard scales applied to the intensity data.
_diffrn_standards_scale_u
CIF
The standard uncertainty of the individual mean
standard scales applied to the intensity data.
_EXPTL_[]
CIF
Data items in the EXPTL category record details about the
experimental work prior to the intensity measurements and details about the absorption-correction technique employed.
Example:
_exptl_absorpt_coefficient_mu 0.962 _exptl_absorpt_correction_type psi-scan _exptl_absorpt_process_details 'North, Phillips & Mathews (1968)' _exptl_absorpt_correction_T_min 0.929 _exptl_absorpt_correction_T_max 0.997
_exptl_absorpt_coefficient_mu
CIF
The absorption coefficient mu in reciprocal millimetres
calculated from the atomic content of the cell, the density and the radiation wavelength.
_exptl_absorpt_correction_T
CIF
Data names: _exptl_absorpt_correction_T_max _exptl_absorpt_correction_T_min
The maximum and minimum transmission factors applied to the
diffraction pattern measured in this experiment. These factors are also referred to as the absorption correction A or 1/A*. As this value is the one that is applied to the measured intensities, it includes the correction for absorption by the specimen mount and diffractometer as well as by the specimen itself.
_exptl_absorpt_correction_type
CIF
The absorption-correction type and method. The value 'empirical'
should NOT be used unless more detailed information is not available.
_exptl_absorpt_process_details
CIF
Description of the absorption process applied to the
intensities. A literature reference should be supplied for psi-scan techniques.
Examples:
Tompa analytical
MolEN (Fair, 1990)
(North, Phillips & Mathews, 1968)
_exptl_crystals_number
CIF
The total number of crystals used for the measurement of
intensities.
_exptl_special_details
CIF
Any special information about the experimental work prior to the
intensity measurements. See also _exptl_crystal_preparation.
_exptl_transmission_factor_max
CIF
The calculated maximum value of the transmission factor for
the specimen. Its value does not include the effects of
absorption in the specimen mount. The presence of this
item does not imply that the structure factors have been
corrected for absorption. The applied correction should be
given by _exptl_absorpt_correction_T_max.
_exptl_transmission_factor_min
CIF
The calculated minimum value of the transmission factor for
the specimen. Its value does not include the effects of
absorption in the specimen mount. The presence of this
item does not imply that the structure factors have been
corrected for absorption. The applied correction should be
given by _exptl_absorpt_correction_T_min.
_EXPTL_CRYSTAL_[]
CIF
Data items in the EXPTL_CRYSTAL category record details about
experimental measurements on the crystal or crystals used, such as shape, size or density.
Examples:
_exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 0.32 _exptl_crystal_size_mid 0.27 _exptl_crystal_size_min 0.10 _exptl_crystal_density_diffrn 1.146 _exptl_crystal_density_meas ? _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 656
_exptl_crystal_density_meas_gt 2.5 _exptl_crystal_density_meas_lt 5.0
_exptl_crystal_density_meas_temp_lt 300
_exptl_crystal_colour
CIF
The colour of the crystal.
Example:
dark green
_exptl_crystal_colour_lustre
CIF
The enumeration list of standardized names developed for the
International Centre for Diffraction Data. The colour of a crystal is given by the combination of _exptl_crystal_colour_modifier with _exptl_crystal_colour_primary, as in 'dark-green' or 'bluish-violet', if necessary combined with _exptl_crystal_colour_lustre, as in 'metallic-green'.
_exptl_crystal_colour_modifier
CIF
The enumeration list of standardized names developed for the
International Centre for Diffraction Data. The colour of a crystal is given by the combination of _exptl_crystal_colour_modifier with _exptl_crystal_colour_primary, as in 'dark-green' or 'bluish-violet', if necessary combined with _exptl_crystal_colour_lustre, as in 'metallic-green'.
_exptl_crystal_colour_primary
CIF
The enumeration list of standardized names developed for the
International Centre for Diffraction Data. The colour of a crystal is given by the combination of _exptl_crystal_colour_modifier with _exptl_crystal_colour_primary, as in 'dark-green' or 'bluish-violet', if necessary combined with _exptl_crystal_colour_lustre, as in 'metallic-green'.
_exptl_crystal_density_diffrn
CIF
Density values calculated from the crystal cell and contents. The
units are megagrams per cubic metre (grams per cubic centimetre).
_exptl_crystal_density_meas
CIF
Density values measured using standard chemical and physical
methods. The units are megagrams per cubic metre (grams per cubic centimetre).
_exptl_crystal_density_meas_gt
CIF
The value above which the density measured using standard
chemical and physical methods lies. The units are megagrams per cubic metre (grams per cubic centimetre). _exptl_crystal_density_meas_gt and _exptl_crystal_density_meas_lt should not be used to report new experimental work, for which _exptl_crystal_density_meas should be used. These items are intended for use in reporting information in existing databases and archives which would be misleading if reported under _exptl_crystal_density_meas.
Example:
2.5
_exptl_crystal_density_meas_lt
CIF
The value below which the density measured using standard
chemical and physical methods lies. The units are megagrams per cubic metre (grams per cubic centimetre). _exptl_crystal_density_meas_gt and _exptl_crystal_density_meas_lt should not be used to report new experimental work, for which _exptl_crystal_density_meas should be used. These items are intended for use in reporting information in existing databases and archives which would be misleading if reported under _exptl_crystal_density_meas.
Examples:
1.0
5.0
_exptl_crystal_density_meas_temp
CIF
Temperature in kelvins at which _exptl_crystal_density_meas
was determined.
_exptl_crystal_density_meas_temp_gt
CIF
Temperature in kelvins above which _exptl_crystal_density_meas
was determined. _exptl_crystal_density_meas_temp_gt and _exptl_crystal_density_meas_temp_lt should not be used for reporting new work, for which the correct temperature of measurement should be given. These items are intended for use in reporting information stored in databases or archives which would be misleading if reported under _exptl_crystal_density_meas_temp.
_exptl_crystal_density_meas_temp_lt
CIF
Temperature in kelvins below which _exptl_crystal_density_meas
was determined. _exptl_crystal_density_meas_temp_gt and _exptl_crystal_density_meas_temp_lt should not be used for reporting new work, for which the correct temperature of measurement should be given. These items are intended for use in reporting information stored in databases or archives which would be misleading if reported under _exptl_crystal_density_meas_temp.
Example:
300
_exptl_crystal_density_method
CIF
The method used to measure _exptl_crystal_density_meas.
Examples:
flotation in aqueous KI
not measured
Berman density torsion balance
_exptl_crystal_description
CIF
A description of the quality and habit of the crystal.
The crystal dimensions should not normally be reported here; use instead _exptl_crystal_size_ for the gross dimensions of the crystal and _exptl_crystal_face_ to describe the relationship between individual faces.
_exptl_crystal_F_000
CIF
The expression for a structure factor evaluated in the
zeroth-order case h = k = l = 0, F(000). This may contain dispersion contributions and is calculated as
F(000) = [ (sum f~r~)^2^ + (sum f~i~)^2^ ]^1/2^
f~r~ = real part of the scattering factors at theta = 0 f~i~ = imaginary part of the scattering factors at theta = 0
the sum is taken over each atom in the unit cell
For X-rays, non-dispersive F(000) is a positive number and counts the effective number of electrons in the unit cell; for neutrons, non-dispersive F(000) (which may be negative) counts the total nuclear scattering power in the unit cell. See http://reference.iucr.org/dictionary/F(000)
_exptl_crystal_id
CIF
Code identifying each crystal if multiple crystals are used. It
is used to link with _diffrn_refln_crystal_id in the intensity measurements and with _refln_crystal_id in the _refln_ list.
_exptl_crystal_preparation
CIF
Details of crystal growth and preparation of the crystal (e.g.
mounting) prior to the intensity measurements.
Example:
mounted in an argon-filled quartz capillary
_exptl_crystal_pressure_history
CIF
Relevant details concerning the pressure history of the
sample.
_exptl_crystal_recrystallization_method
CIF
Describes the method used to recrystallize the sample.
Sufficient details should be given for the procedure to be repeated. The temperature or temperatures should be given as well as details of the solvent, flux or carrier gas with concentrations or pressures and ambient atmosphere.
_exptl_crystal_size
CIF
Data names: _exptl_crystal_size_length _exptl_crystal_size_max _exptl_crystal_size_mid _exptl_crystal_size_min _exptl_crystal_size_rad
The maximum, medial and minimum dimensions in millimetres of
the crystal. If the crystal is a sphere, then the *_rad item is
its radius. If the crystal is a cylinder, then the *_rad item
is its radius and the *_length item is its length. These may
appear in a list with _exptl_crystal_id if multiple crystals
are used in the experiment.
_exptl_crystal_thermal_history
CIF
Relevant details concerning the thermal history of the
sample.
_EXPTL_CRYSTAL_FACE_[]
CIF
Data items in the EXPTL_CRYSTAL_FACE category record details
of the crystal faces.
Example:
loop_
_exptl_crystal_face_index_h
_exptl_crystal_face_index_k
_exptl_crystal_face_index_l
_exptl_crystal_face_perp_dist
0 -1 -2 .18274
1 0 -2 .17571
-1 1 -2 .17845
-2 1 0 .21010
-1 0 2 .18849
1 -1 2 .20605
2 -1 0 .24680
-1 2 0 .19688
0 1 2 .15206
_exptl_crystal_face_diffr
CIF
Data names: _exptl_crystal_face_diffr_chi _exptl_crystal_face_diffr_kappa _exptl_crystal_face_diffr_phi _exptl_crystal_face_diffr_psi
The goniometer angle settings in degrees when the perpendicular
to the specified crystal face is aligned along a specified direction (e.g. the bisector of the incident and reflected beams in an optical goniometer).
_exptl_crystal_face_index
CIF
Data names: _exptl_crystal_face_index_h _exptl_crystal_face_index_k _exptl_crystal_face_index_l
Miller indices of the crystal face associated with the value
_exptl_crystal_face_perp_dist.
_exptl_crystal_face_perp_dist
CIF
The perpendicular distance in millimetres from the face to the
centre of rotation of the crystal.
_GEOM_[]
CIF
Data items in the GEOM and related (GEOM_ANGLE,
GEOM_BOND, GEOM_CONTACT, GEOM_HBOND and GEOM_TORSION) categories record details about the molecular and crystal geometry as calculated from the ATOM, CELL and SYMMETRY data.
Geometry data are usually redundant, in that they can be calculated from other more fundamental quantities in the data block. However, they serve the dual purposes of providing a check on the correctness of both sets of data and of enabling the most important geometric data to be identified for publication by setting the appropriate publication flag.
Example:
_geom_special_details
; All esds (except the esd in the dihedral angle between
two l.s. planes) are estimated using the full covariance
matrix. The cell esds are taken into account individually
in the estimation of esds in distances, angles and
torsion angles; correlations between esds in cell
parameters are only used when they are defined by crystal
symmetry. An approximate (isotropic) treatment of cell
esds is used for estimating esds involving l.s. planes.
;
_geom_special_details
CIF
The description of geometrical information not covered by the
existing data names in the geometry categories, such as least-squares planes.
_GEOM_ANGLE_[]
CIF
Data items in the GEOM_ANGLE category record details about the
bond angles as calculated from the ATOM, CELL and SYMMETRY data.
Example:
loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_2
_geom_angle_site_symmetry_3
_geom_angle_publ_flag
C2 O1 C5 111.6(2) 1_555 1_555 1_555 yes
O1 C2 C3 110.9(2) 1_555 1_555 1_555 yes
O1 C2 O21 122.2(3) 1_555 1_555 1_555 yes
C3 C2 O21 127.0(3) 1_555 1_555 1_555 yes
C2 C3 N4 101.3(2) 1_555 1_555 1_555 yes
C2 C3 C31 111.3(2) 1_555 1_555 1_555 yes
C2 C3 H3 107(1) 1_555 1_555 1_555 no
N4 C3 C31 116.7(2) 1_555 1_555 1_555 yes
# - - - - data truncated for brevity - - - -
_geom_angle
CIF
Angle in degrees defined by the three sites
_geom_angle_atom_site_label_1, *_2 and *_3. The site at *_2
is at the apex of the angle.
_geom_angle_atom_site_label
CIF
Data names: _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3
The labels of the three atom sites which define the angle
given by _geom_angle. These must match labels specified as _atom_site_label in the atom list. Label 2 identifies the site at the apex of the angle.
_geom_angle_publ_flag
CIF
This code signals whether the angle is referred to in a
publication or should be placed in a table of significant angles.
_geom_angle_site_symmetry
CIF
Data names: _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_2 _geom_angle_site_symmetry_3
The symmetry code of each atom site as the symmetry-equivalent
position number 'n' and the cell translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character string n_klm is composed as follows:
n refers to the symmetry operation that is applied to the coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a number given in _space_group_symop_id.
k, l and m refer to the translations that are subsequently
applied to the symmetry-transformed coordinates to generate
the atom used in calculating the angle. These translations
(x,y,z) are related to (k,l,m) by the relations
k = 5 + x
l = 5 + y
m = 5 + z
By adding 5 to the translations, the use of negative numbers
is avoided.
Examples:
4
7_645
_GEOM_BOND_[]
CIF
Data items in the GEOM_BOND category record details about
bonds as calculated from the ATOM, CELL and SYMMETRY data.
Examples:
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_1
_geom_bond_site_symmetry_2
_geom_bond_publ_flag
O1 C2 1.342(4) 1_555 1_555 yes
O1 C5 1.439(3) 1_555 1_555 yes
C2 C3 1.512(4) 1_555 1_555 yes
C2 O21 1.199(4) 1_555 1_555 yes
C3 N4 1.465(3) 1_555 1_555 yes
C3 C31 1.537(4) 1_555 1_555 yes
C3 H3 1.00(3) 1_555 1_555 no
N4 C5 1.472(3) 1_555 1_555 yes
# - - - - data truncated for brevity - - - -
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_multiplicity
Ca1 F1 2.495(9) 1
Ca1 F2 2.291(10) 2
Ca1 F2 2.391(11) 2
Ca1 F3 2.214(11) 2
Cr1 F1 1.940(11) 2
Cr1 F2 1.918(9) 2
Cr1 F3 1.848(10) 2
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_site_symmetry_2
_geom_bond_distance
_geom_bond_multiplicity
Ca1 F1 1_555 2.495(9) 1
Ca1 F2 1_555 2.291(10) 2
Ca1 F2 2_555 2.291(10) 0
Ca1 F2 3_565 2.391(11) 2
Ca1 F2 4_555 2.391(11) 0
Ca1 F3 2_545 2.214(11) 2
Ca1 F3 5_555 2.214(11) 0
Cr1 F1 1_555 1.940(11) 2
Cr1 F1 2_555 1.940(11) 0
Cr1 F2 1_555 1.918(9) 2
Cr1 F2 2_555 1.918(9) 0
Cr1 F3 1_555 1.848(10) 2
Cr1 F3 2_555 1.848(10) 0
_geom_bond_atom_site_label
CIF
Data names: _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2
The labels of two atom sites that form a bond. These must match
labels specified as _atom_site_label in the atom list.
_geom_bond_distance
CIF
The intramolecular bond distance in angstroms.
_geom_bond_multiplicity
CIF
The number of times the given bond appears in the environment
of the atoms labelled _geom_bond_atom_site_label_1. In cases
where the full list of bonds is given, one of the series of
equivalent bonds may be assigned the appropriate multiplicity
while the others are assigned a value of 0.
_geom_bond_publ_flag
CIF
This code signals whether the bond distance is referred to in a
publication or should be placed in a list of significant bond distances.
_geom_bond_site_symmetry
CIF
Data names: _geom_bond_site_symmetry_1 _geom_bond_site_symmetry_2
The symmetry code of each atom site as the symmetry-equivalent
position number 'n' and the cell translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character string n_klm is composed as follows:
n refers to the symmetry operation that is applied to the coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a number given in _space_group_symop_id.
k, l and m refer to the translations that are subsequently
applied to the symmetry-transformed coordinates to generate
the atom used in calculating the bond. These translations
(x,y,z) are related to (k,l,m) by the relations
k = 5 + x
l = 5 + y
m = 5 + z
By adding 5 to the translations, the use of negative numbers
is avoided.
Examples:
4
7_645
_geom_bond_valence
CIF
The bond valence calculated from _geom_bond_distance.
_GEOM_CONTACT_[]
CIF
Data items in the GEOM_CONTACT category record details about
interatomic contacts as calculated from the ATOM, CELL and SYMMETRY data.
Example:
loop_
_geom_contact_atom_site_label_1
_geom_contact_atom_site_label_2
_geom_contact_distance
_geom_contact_site_symmetry_1
_geom_contact_site_symmetry_2
_geom_contact_publ_flag
O(1) O(2) 2.735(3) . . yes
H(O1) O(2) 1.82 . . no
_geom_contact_atom_site_label
CIF
Data names: _geom_contact_atom_site_label_1 _geom_contact_atom_site_label_2
The labels of two atom sites that are within contact distance.
The labels must match _atom_site_label codes in the atom list.
_geom_contact_distance
CIF
The interatomic contact distance in angstroms.
_geom_contact_publ_flag
CIF
This code signals whether the contact distance is referred to
in a publication or should be placed in a list of significant contact distances.
_geom_contact_site_symmetry
CIF
Data names: _geom_contact_site_symmetry_1 _geom_contact_site_symmetry_2
The symmetry code of each atom site as the symmetry-equivalent
position number 'n' and the cell translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character string n_klm is composed as follows:
n refers to the symmetry operation that is applied to the coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a number given in _space_group_symop_id.
k, l and m refer to the translations that are subsequently
applied to the symmetry-transformed coordinates to generate
the atom used in calculating the contact. These translations
(x,y,z) are related to (k,l,m) by the relations
k = 5 + x
l = 5 + y
m = 5 + z
By adding 5 to the translations, the use of negative numbers
is avoided.
Examples:
4
7_645
_GEOM_HBOND_[]
CIF
Data items in the GEOM_HBOND category record details about
hydrogen bonds as calculated from the ATOM, CELL and SYMMETRY data.
Example:
loop_
_geom_hbond_atom_site_label_D
_geom_hbond_atom_site_label_H
_geom_hbond_atom_site_label_A
_geom_hbond_distance_DH
_geom_hbond_distance_HA
_geom_hbond_distance_DA
_geom_hbond_angle_DHA
_geom_hbond_publ_flag
N6 HN6 OW 0.888(8) 1.921(12) 2.801(8) 169.6(8) yes
OW HO2 O7 0.917(6) 1.923(12) 2.793(8) 153.5(8) yes
OW HO1 N10 0.894(8) 1.886(11) 2.842(8) 179.7(9) yes
_geom_hbond_angle_DHA
CIF
Angle in degrees defined by the three sites
_geom_hbond_atom_site_label_D, *_H and *_A. The site at *_H
(the hydrogen atom participating in the interaction) is at
the apex of the angle.
_geom_hbond_atom_site_label
CIF
Data names: _geom_hbond_atom_site_label_D _geom_hbond_atom_site_label_H _geom_hbond_atom_site_label_A
The labels of three atom sites (respectively, the donor atom,
hydrogen atom and acceptor atom) participating in a hydrogen
bond. These must match labels specified as _atom_site_label
in the atom list.
_geom_hbond_distance
CIF
Data names: _geom_hbond_distance_DH _geom_hbond_distance_HA _geom_hbond_distance_DA
Distances in angstroms between the donor and hydrogen (*_DH),
hydrogen and acceptor (*_HA) and donor and acceptor (*_DA) sites in a hydrogen bond.
_geom_hbond_publ_flag
CIF
This code signals whether the hydrogen-bond information
is referred to in a publication or should be placed in a table of significant hydrogen-bond geometry.
_geom_hbond_site_symmetry
CIF
Data names: _geom_hbond_site_symmetry_D _geom_hbond_site_symmetry_H _geom_hbond_site_symmetry_A
The symmetry code of each atom site as the symmetry-equivalent
position number 'n' and the cell translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character string n_klm is composed as follows:
n refers to the symmetry operation that is applied to the coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a number given in _space_group_symop_id.
k, l and m refer to the translations that are subsequently
applied to the symmetry-transformed coordinates to generate
the atom used in calculating the hydrogen bond. These
translations (x,y,z) are related to (k,l,m) by the relations
k = 5 + x
l = 5 + y
m = 5 + z
By adding 5 to the translations, the use of negative numbers
is avoided.
Examples:
4
7_645
_GEOM_TORSION_[]
CIF
Data items in the GEOM_TORSION category record details about
interatomic torsion angles as calculated from the ATOM, CELL and SYMMETRY data.
Example:
loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
_geom_torsion
_geom_torsion_site_symmetry_1
_geom_torsion_site_symmetry_2
_geom_torsion_site_symmetry_3
_geom_torsion_site_symmetry_4
_geom_torsion_publ_flag
C(9) O(2) C(7) C(2) 71.8(2) . . . . yes
C(7) O(2) C(9) C(10) -168.0(3) . . . 2_666 yes
C(10) O(3) C(8) C(6) -167.7(3) . . . . yes
C(8) O(3) C(10) C(9) -69.7(2) . . . 2_666 yes
O(1) C(1) C(2) C(3) -179.5(4) . . . . no
O(1) C(1) C(2) C(7) -0.6(1) . . . . no
_geom_torsion
CIF
The torsion angle in degrees bounded by the four atom sites
identified by the _geom_torsion_atom_site_label_ codes. These
must match labels specified as _atom_site_label in the atom list.
The torsion-angle definition should be that of Klyne and Prelog.
Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521-523.
_geom_torsion_atom_site_label
CIF
Data names: _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4
The labels of the four atom sites which define the torsion angle
specified by _geom_torsion. These must match codes specified as _atom_site_label in the atom list. The torsion-angle definition should be that of Klyne and Prelog. The vector direction *_label_2 to *_label_3 is the viewing direction, and the torsion angle is the angle of twist required to superimpose the projection of the vector between site 2 and site 1 onto the projection of the vector between site 3 and site 4. Clockwise torsions are positive, anticlockwise torsions are negative.
Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521-523.
_geom_torsion_publ_flag
CIF
This code signals whether the torsion angle is referred to in a
publication or should be placed in a table of significant torsion angles.
_geom_torsion_site_symmetry
CIF
Data names: _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4
The symmetry code of each atom site as the symmetry-equivalent
position number 'n' and the cell translation number 'klm'. These numbers are combined to form the code 'n klm' or n_klm. The character string n_klm is composed as follows:
n refers to the symmetry operation that is applied to the coordinates stored in _atom_site_fract_x, _atom_site_fract_y and _atom_site_fract_z. It must match a number given in _space_group_symop_id.
k, l and m refer to the translations that are subsequently
applied to the symmetry-transformed coordinates to generate
the atom used in calculating the angle. These translations
(x,y,z) are related to (k,l,m) by the relations
k = 5 + x
l = 5 + y
m = 5 + z
By adding 5 to the translations, the use of negative numbers
is avoided.
Examples:
4
7_645
_JOURNAL_[]
CIF
Data items in the JOURNAL category record details about the
book-keeping by the journal staff when processing a CIF submitted for publication.
The creator of a CIF will not normally specify these data items. The data names are not defined in the dictionary because they are for journal use only.
Example:
_journal_date_recd_electronic 91-04-15 _journal_date_from_coeditor 91-04-18 _journal_date_accepted 91-04-18 _journal_date_printers_first 91-08-07 _journal_date_proofs_out 91-08-07 _journal_coeditor_code HL0007 _journal_techeditor_code C910963 _journal_coden_ASTM ACSCEE _journal_name_full 'Acta Crystallographica Section C' _journal_year 1991 _journal_volume 47 _journal_issue NOV91 _journal_page_first 2276 _journal_page_last 2277
_journal
CIF
Data names: _journal_coden_ASTM _journal_coden_Cambridge _journal_coeditor_address _journal_coeditor_code _journal_coeditor_email _journal_coeditor_fax _journal_coeditor_name _journal_coeditor_notes _journal_coeditor_phone _journal_data_validation_number _journal_date_accepted _journal_date_from_coeditor _journal_date_to_coeditor _journal_date_printers_final _journal_date_printers_first _journal_date_proofs_in _journal_date_proofs_out _journal_date_recd_copyright _journal_date_recd_electronic _journal_date_recd_hard_copy _journal_issue _journal_language _journal_name_full _journal_page_first _journal_page_last _journal_paper_category _journal_paper_doi _journal_suppl_publ_number _journal_suppl_publ_pages _journal_techeditor_address _journal_techeditor_code _journal_techeditor_email _journal_techeditor_fax _journal_techeditor_name _journal_techeditor_notes _journal_techeditor_phone _journal_volume _journal_year
Data items specified by the journal staff.
_JOURNAL_INDEX_[]
CIF
Data items in the JOURNAL_INDEX category are used to list
terms used to generate the journal indexes.
The creator of a CIF will not normally specify these data items.
Example:
loop_
_journal_index_type
_journal_index_term
_journal_index_subterm
O C16H19NO4 .
S alkaloids (-)-norcocaine
S (-)-norcocaine .
S
; [2R,3S-(2β,3β)]-methyl
3-(benzoyloxy)-8-azabicyclo[3.2.1]octane-2-carboxylate
; .
_journal_index
CIF
Data names: _journal_index_subterm _journal_index_term _journal_index_type
Indexing terms supplied by the journal staff.
_PUBL_[]
CIF
Data items in the PUBL category are used when submitting a
manuscript for publication. They refer either to the paper as a whole, or to specific named elements within a paper (such as the title and abstract, or the Comment and Experimental sections of Acta Crystallographica Section C). The data items in the PUBL_BODY category should be used for the text of other submissions. Typically, each journal will supply a list of the specific items it requires in its Notes for Authors.
Examples:
_publ_section_title
; trans-3-Benzoyl-2-(tert-butyl)-4-(iso-butyl)-
1,3-oxazolidin-5-one
;
_publ_section_abstract
; The oxazolidinone ring is a shallow envelope
conformation with the tert-butyl and iso-butyl groups
occupying trans-positions with respect to the ring. The
angles at the N atom sum to 356.2°, indicating a very
small degree of pyramidalization at this atom. This is
consistent with electron delocalization between the N
atom and the carbonyl centre [N-C=O = 1.374(3)Å].
;
_publ_section_title
; Hemiasterlin methyl ester
;
_publ_section_title_footnote
; IUPAC name: methyl 2,5-dimethyl-4-{2-[3-methyl-
2-methylamino-3-(N-methylbenzo[b]pyrrol-
3-yl)butanamido]-3,3-dimethyl-N-methyl-
butanamido}-2-hexenoate.
;
_publ_contact_author
CIF
The name and address of the author submitting the manuscript and
data block. This is the person contacted by the journal editorial staff. It is preferable to use the separate data items _publ_contact_author_name and _publ_contact_author_address.
Example:
Professor George Ferguson
Department of Chemistry and Biochemistry
University of Guelph
Ontario
Canada
N1G 2W1
_publ_contact_author_address
CIF
The address of the author submitting the manuscript and
data block. This is the person contacted by the journal editorial staff.
Example:
Department of Chemistry and Biochemistry
University of Guelph
Ontario
Canada
N1G 2W1
_publ_contact_author_email
CIF
E-mail address in a form recognizable to international networks.
The format of e-mail addresses is given in Section 3.4, Address Specification, of Internet Message Format, RFC 2822, P. Resnick (Editor), Network Standards Group, April 2001.
Examples:
_publ_contact_author_fax
CIF
Facsimile telephone number of the author submitting the
manuscript and data block.
The recommended style is the international dialing prefix, followed by the area code in parentheses, followed by the local number with no spaces. The earlier convention of including the international dialing prefix in parentheses is no longer recommended.
Examples:
12(34)9477334
12()349477334
_publ_contact_author_id_iucr
CIF
Identifier in the IUCr contact database of the author
submitting the manuscript and data block. This identifier may be available from the World Directory of Crystallographers (http://wdc.iucr.org).
Example:
2985
_publ_contact_author_id_orcid
CIF
Identifier in the ORCID Registry of the author submitting
the manuscript and data block. ORCID is an open, non-profit, community-driven service to provide a registry of unique researcher identifiers (http://orcid.org).
Example:
0000-0003-0391-0002
_publ_contact_author_name
CIF
The name of the author submitting the manuscript and
data block. This is the person contacted by the journal editorial staff.
Example:
Professor George Ferguson
_publ_contact_author_phone
CIF
Telephone number of the author submitting the manuscript and
data block.
The recommended style is the international dialing prefix, followed by the area code in parentheses, followed by the local number and any extension number prefixed by 'x', with no spaces. The earlier convention of including the international dialing prefix in parentheses is no longer recommended.
Examples:
12(34)9477330
12()349477330
12(34)9477330x5543
_publ_contact_letter
CIF
A letter submitted to the journal editor by the contact author.
_publ_manuscript_creation
CIF
A description of the word-processor package and computer used to
create the word-processed manuscript stored as
_publ_manuscript_processed.
Example:
Tex file created by FrameMaker on a Sun 3/280
_publ_manuscript_processed
CIF
The full manuscript of a paper (excluding possibly the figures
and the tables) output in ASCII characters from a word processor.
Information about the generation of this data item must be
specified in the data item _publ_manuscript_creation.
_publ_manuscript_text
CIF
The full manuscript of a paper (excluding figures and possibly
the tables) output as standard ASCII text.
_publ_requested_category
CIF
The category of paper submitted. For submission to Acta
Crystallographica Section C or Acta Crystallographica Section E, ONLY those codes indicated for use with those journals should be used.
_publ_requested_coeditor_name
CIF
The name of the co-editor whom the authors would like to
handle the submitted manuscript.
_publ_requested_journal
CIF
The name of the journal to which the manuscript is being
submitted.
_PUBL_AUTHOR_[]
CIF
Data items in the PUBL_AUTHOR category record details of
the authors of a manuscript submitted for publication.
Example:
loop_
_publ_author_name
_publ_author_address
'Willis, Anthony C.'
; Research School of Chemistry
Australian National University
GPO Box 4
Canberra, ACT
Australia 2601
;
_publ_author_address
CIF
The address of a publication author. If there is more than one
author, this will be looped with _publ_author_name.
Example:
Department
Institute
Street
City and postcode
COUNTRY
_publ_author_email
CIF
The e-mail address of a publication author. If there is more
than one author, this will be looped with _publ_author_name.
The format of e-mail addresses is given in Section 3.4, Address
Specification, of Internet Message Format, RFC 2822, P. Resnick
(Editor), Network Standards Group, April 2001.
Examples:
_publ_author_footnote
CIF
A footnote accompanying an author's name in the list of authors
of a paper. Typically indicates sabbatical address, additional affiliations or date of decease.
Examples:
On leave from U. Western Australia
Also at Department of Biophysics
_publ_author_id_iucr
CIF
Identifier in the IUCr contact database of a publication
author. This identifier may be available from the World Directory of Crystallographers (http://wdc.iucr.org).
Example:
2985
_publ_author_id_orcid
CIF
Identifier in the ORCID Registry of a publication
author. ORCID is an open, non-profit, community-driven service to provide a registry of unique researcher identifiers (http://orcid.org).
Example:
0000-0003-0391-0002
_publ_author_name
CIF
The name of a publication author. If there are multiple authors,
this will be looped with _publ_author_address. The family
name(s), followed by a comma and including any dynastic
components, precedes the first names or initials.
Examples:
Bleary, Percival R.
O'Neil, F.K.
Van den Bossche, G.
Yang, D.-L.
Simonov, Yu.A.
Müller, H.A.
Ross II, C.R.
_PUBL_BODY_[]
CIF
Data items in the PUBL_BODY category permit the labelling of
different text sections within the body of a paper. Note that these should not be used in a paper which has a standard format with sections tagged by specific data names (such as in Acta Crystallographica Section C). Typically, each journal will supply a list of the specific items it requires in its Notes for Authors.
Examples:
loop_
_publ_body_element
_publ_body_label
_publ_body_title
_publ_body_format
_publ_body_contents
section 1 Introduction cif
; X-ray diffraction from a crystalline material provides
information on the thermally and spatially averaged
electron density in the crystal...
;
section 2 Theory tex
; In the rigid-atom approximation, the dynamic electron
density of an atom is described by the convolution
product of the static atomic density and a probability
density function,
$ρho_{dyn}(βf r) = ρho_{stat}(βf r) * P(βf r). εqno(1)$
;
loop_
_publ_body_element
_publ_body_label
_publ_body_title
_publ_body_contents
section 3
; The two-channel method for retrieval of the deformation
electron density
;
.
subsection 3.1 'The two-channel entropy S[Δρ(r)]'
; As the wide dynamic range involved in the total electron
density...
;
subsection 3.2
'Uniform vs informative prior model densities' .
subsubsection 3.2.1 'Use of uniform models'
; Straightforward algebra leads to expressions analogous
to...
;
_publ_body_contents
CIF
A text section of a paper.
_publ_body_element
CIF
The functional role of the associated text section.
_publ_body_format
CIF
Code indicating the appropriate typesetting conventions
for accented characters and special symbols in the text section.
_publ_body_label
CIF
Code identifying the section of text. The combination of this
with _publ_body_element must be unique.
Examples:
1
1.1
2.1.3
_publ_body_title
CIF
Title of the associated section of text.
_PUBL_MANUSCRIPT_INCL_[]
CIF
Data items in the PUBL_MANUSCRIPT_INCL category allow
the authors of a manuscript submitted for publication to list data names that should be added to the standard request list used by the journal printing software. Although these fields are primarily intended to identify CIF data items that the author wishes to include in a published paper, they can also be used to identify data names created so that non-CIF items can be included in the publication. Note that *_item names MUST be enclosed in single quotes.
Examples:
loop_
_publ_manuscript_incl_extra_item
_publ_manuscript_incl_extra_info
_publ_manuscript_incl_extra_defn
#
# Include Hydrogen Bonding Geometry Description
# =============================================
# Name explanation standard?
# ---- ----------- ---------
'_geom_hbond_atom_site_label_D' 'H-bond donor' yes
'_geom_hbond_atom_site_label_H' 'H-bond hydrogen' yes
'_geom_hbond_atom_site_label_A' 'H-bond acceptor' yes
'_geom_hbond_distance_DH' 'H-bond D-H' yes
'_geom_hbond_distance_HA' 'H-bond H...A' yes
'_geom_hbond_distance_DA' 'H-bond D...A' yes
'_geom_hbond_angle_DHA' 'H-bond D-H...A' yes
loop_
_publ_manuscript_incl_extra_item
_publ_manuscript_incl_extra_info
_publ_manuscript_incl_extra_defn
'_atom_site_site_symmetry_multiplicity'
'to emphasise special sites' yes
'_chemical_compound_source'
'rare material, unusual source' yes
'_reflns_d_resolution_high'
'limited data is a problem here' yes
'_crystal_magnetic_permeability'
'unusual value for this material' no
_publ_manuscript_incl_extra_defn
CIF
Flags whether the corresponding data item marked for inclusion
in a journal request list is a standard CIF definition or not.
_publ_manuscript_incl_extra_info
CIF
A short note indicating the reason why the author wishes the
corresponding data item marked for inclusion in the journal request list to be published.
_publ_manuscript_incl_extra_item
CIF
Specifies the inclusion of specific data into a manuscript
which are not normally requested by the journal. The values of this item are the extra data names (which MUST be enclosed in single quotes) that will be added to the journal request list.
_REFINE_[]
CIF
Data items in the REFINE category record details about the
structure-refinement parameters.
Example:
_refine_special_details sfls:_F_calc_weight_full_matrix
_refine_ls_structure_factor_coef F _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'w=1/(u^2^(F)+0.0004F^2^)' _refine_ls_hydrogen_treatment refxyz _refine_ls_extinction_method Zachariasen _refine_ls_extinction_coef 3514(42) _refine_ls_extinction_expression ; Larson, A. C. (1970). "Crystallographic Computing", edited by F. R. Ahmed. Eq. (22) p. 292. Copenhagen: Munksgaard. ; _refine_ls_abs_structure_details ; The absolute configuration was assigned to agree with that of its precursor l-leucine at the chiral centre C3. ; _refine_ls_number_reflns 1408 _refine_ls_number_parameters 272 _refine_ls_number_restraints 0 _refine_ls_number_constraints 0 _refine_ls_R_factor_all .038 _refine_ls_R_factor_gt .034 _refine_ls_wR_factor_all .044 _refine_ls_wR_factor_gt .042 _refine_ls_goodness_of_fit_all 1.462 _refine_ls_goodness_of_fit_gt 1.515 _refine_ls_shift/su_max .535 _refine_ls_shift/su_mean .044 _refine_diff_density_min -.108 _refine_diff_density_max .131
_refine_diff_density
CIF
Data names: _refine_diff_density_max _refine_diff_density_min _refine_diff_density_rms
The largest and smallest values and the root-mean-square
deviation, in electrons per angstrom cubed, of the final difference electron density. The *_rms value is measured with respect to the arithmetic mean density and is derived from summations over each grid point in the asymmetric unit of the cell. This quantity is useful for assessing the significance of *_min and *_max values, and also for defining suitable contour levels.
_refine_ls_abs_structure_details
CIF
The nature of the absolute structure and how it was determined.
_refine_ls_abs_structure_Flack
CIF
The measure of absolute structure as defined by Flack (1983).
For centrosymmetric structures, the only permitted value, if the data name is present, is 'inapplicable', represented by '.' .
For noncentrosymmetric structures, the value must lie in the 99.97% Gaussian confidence interval -3u =< x =< 1 + 3u and a standard uncertainty (e.s.d.) u must be supplied. The _enumeration_range of 0.0:1.0 is correctly interpreted as meaning (0.0 - 3u) =< x =< (1.0 + 3u).
Ref: Flack, H. D. (1983). Acta Cryst. A39, 876-881.
_refine_ls_abs_structure_Rogers
CIF
The measure of absolute structure as defined by Rogers (1981).
The value must lie in the 99.97% Gaussian confidence interval -1 -3u =< η =< 1 + 3u and a standard uncertainty (e.s.d.) u must be supplied. The _enumeration_range of -1.0:1.0 is correctly interpreted as meaning (-1.0 - 3u) =< η =< (1.0 + 3u).
Ref: Rogers, D. (1981). Acta Cryst. A37, 734-741.
_refine_ls_d_res_high
CIF
The smallest value in angstroms of the interplanar spacings
of the reflections used in the refinement. This is called the highest resolution.
_refine_ls_d_res_low
CIF
The largest value in angstroms of the interplanar spacings
of the reflections used in the refinement. This is called the lowest resolution.
_refine_ls_extinction_coef
CIF
The extinction coefficient used to calculate the correction
factor applied to the structure-factor data. The nature of the extinction coefficient is given in the definitions of _refine_ls_extinction_expression and _refine_ls_extinction_method.
For the 'Zachariasen' method it is the r* value; for the 'Becker-Coppens type 1 isotropic' method it is the 'g' value and for 'Becker-Coppens type 2 isotropic' corrections it is the 'rho' value. Note that the magnitude of these values is usually of the order of 10000.
Ref: Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30,
129-147, 148-153.
Zachariasen, W. H. (1967). Acta Cryst. 23, 558-564.
Larson, A. C. (1967). Acta Cryst. 23, 664-665.
Example:
3472(52)
_refine_ls_extinction_expression
CIF
A description of or reference to the extinction-correction
equation used to apply the data item _refine_ls_extinction_coef.
This information must be sufficient to reproduce the
extinction-correction factors applied to the structure factors.
Example:
Larson, A. C. (1970). "Crystallographic Computing",
edited by F. R. Ahmed. Eq. (22), p. 292.
Copenhagen: Munksgaard.
_refine_ls_extinction_method
CIF
A description of the extinction-correction method applied.
This description should include information about the correction method, either 'Becker-Coppens' or 'Zachariasen'. The latter is sometimes referred to as the 'Larson' method even though it employs Zachariasen's formula.
The Becker-Coppens procedure is referred to as 'type 1' when correcting secondary extinction dominated by the mosaic spread; as 'type 2' when secondary extinction is dominated by particle size and includes a primary extinction component; and as 'mixed' when there is a mixture of types 1 and 2.
For the Becker-Coppens method, it is also necessary to set the
mosaic distribution as either 'Gaussian' or 'Lorentzian' and
the nature of the extinction as 'isotropic' or 'anisotropic'.
Note that if either the 'mixed' or 'anisotropic' corrections
are applied, the multiple coefficients cannot be contained in
*_extinction_coef and must be listed in _refine_special_details.
Ref: Becker, P. J. & Coppens, P. (1974). Acta Cryst. A30,
129-147, 148-153.
Zachariasen, W. H. (1967). Acta Cryst. 23, 558-564.
Larson, A. C. (1967). Acta Cryst. 23, 664-665.
Examples:
B-C type 2 Gaussian isotropic
none
_refine_ls_F_calc_details
CIF
Details concerning the evaluation of the structure
factors using the expression given in
_refine_ls_F_calc_formula.
Examples:
Gaussian integration using 16 points
Bessel functions expansion up to 5th order.
Bessel functions estimated accuracy: better
than 0.001 electrons.
_refine_ls_F_calc_formula
CIF
Analytical expression used to calculate the structure factors.
_refine_ls_F_calc_precision
CIF
This item gives an estimate of the precision resulting
from the numerical approximations made during the evaluation of the structure factors using the expression given in _refine_ls_F_calc_formula following the method outlined in _refine_ls_F_calc_details. For X-ray diffraction the result is given in electrons.
_refine_ls_goodness_of_fit_all
CIF
The least-squares goodness-of-fit parameter S for all
reflections after the final cycle of refinement. Ideally, account should be taken of parameters restrained in the least-squares refinement. See also _refine_ls_restrained_S_ definitions.
{ sum { w [ Y(obs) - Y(calc) ]^2^ } }^1/2^
S = { ----------------------------------- }
{ Nref - Nparam }
Y(obs) = the observed coefficients
(see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients
(see _refine_ls_structure_factor_coef)
w = the least-squares reflection weight
[1/(u^2^)]
u = the standard uncertainty
Nref = the number of reflections used in the refinement Nparam = the number of refined parameters
and the sum is taken over the specified reflections
_refine_ls_goodness_of_fit_gt
CIF
The least-squares goodness-of-fit parameter S for
significantly intense reflections (see
_reflns_threshold_expression) after the final cycle of
refinement. Ideally, account should be taken of parameters
restrained in the least-squares refinement. See also
_refine_ls_restrained_S_ definitions.
{ sum { w [ Y(obs) - Y(calc) ]^2^ } }^1/2^
S = { ----------------------------------- }
{ Nref - Nparam }
Y(obs) = the observed coefficients
(see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients
(see _refine_ls_structure_factor_coef)
w = the least-squares reflection weight
[1/(u^2^)]
u = standard uncertainty
Nref = the number of reflections used in the refinement Nparam = the number of refined parameters
and the sum is taken over the specified reflections
_refine_ls_goodness_of_fit_obs
CIF
The least-squares goodness-of-fit parameter S for observed
reflections (see _reflns_observed_criterion) after the final
cycle of refinement. Ideally, account should be taken of
parameters restrained in the least-squares refinement. See also
_refine_ls_restrained_S_ definitions.
{ sum { w [ Y(obs) - Y(calc) ]^2^ } }^1/2^
S = { ----------------------------------- }
{ Nref - Nparam }
Y(obs) = the observed coefficients
(see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients
(see _refine_ls_structure_factor_coef)
w = the least-squares reflection weight
[1/(u^2^)]
u = standard uncertainty (e.s.d.)
Nref = the number of reflections used in the refinement Nparam = the number of refined parameters
and the sum is taken over the specified reflections
_refine_ls_goodness_of_fit_ref
CIF
The least-squares goodness-of-fit parameter S for all
reflections included in the refinement after the final cycle of refinement. Ideally, account should be taken of parameters restrained in the least-squares refinement. See also _refine_ls_restrained_S_ definitions.
{ sum | w | Y(obs) - Y(calc) |^2^ | }^1/2^
S = { ----------------------------------- }
{ Nref - Nparam }
Y(obs) = the observed coefficients
(see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients
(see _refine_ls_structure_factor_coef)
w = the least-squares reflection weight
[1/(u^2^)]
u = standard uncertainty
Nref = the number of reflections used in the refinement Nparam = the number of refined parameters
and the sum is taken over the specified reflections
_refine_ls_hydrogen_treatment
CIF
Treatment of hydrogen atoms in the least-squares refinement.
_refine_ls_matrix_type
CIF
Type of matrix used to accumulate the least-squares derivatives.
_refine_ls_number_constraints
CIF
The number of constrained (non-refined or dependent) parameters
in the least-squares process. These may be due to symmetry or any other constraint process (e.g. rigid-body refinement). See also _atom_site_constraints and _atom_site_refinement_flags. A general description of constraints may appear in _refine_special_details.
_refine_ls_number_parameters
CIF
The number of parameters refined in the least-squares process.
If possible, this number should include some contribution from the restrained parameters. The restrained parameters are distinct from the constrained parameters (where one or more parameters are linearly dependent on the refined value of another). Least-squares restraints often depend on geometry or energy considerations and this makes their direct contribution to this number, and to the goodness-of-fit calculation, difficult to assess.
_refine_ls_number_reflns
CIF
The number of unique reflections contributing to the
least-squares refinement calculation.
_refine_ls_number_restraints
CIF
The number of restrained parameters. These are parameters which
are not directly dependent on another refined parameter. Restrained parameters often involve geometry or energy dependencies. See also _atom_site_constraints and _atom_site_refinement_flags. A general description of refinement constraints may appear in _refine_special_details.
_refine_ls_R_factor_all
CIF
Residual factor for all reflections satisfying the
resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. This is the conventional R factor. See also _refine_ls_wR_factor_ definitions.
sum | F(obs) - F(calc) |
R = ------------------------
sum | F(obs) |
F(obs) = the observed structure-factor amplitudes F(calc) = the calculated structure-factor amplitudes
and the sum is taken over the specified reflections
_refine_ls_R_factor_gt
CIF
Residual factor for the reflections (with number given by
_reflns_number_gt) judged significantly intense (i.e. satisfying the threshold specified by _reflns_threshold_expression) and included in the refinement. The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. This is the conventional R factor. See also _refine_ls_wR_factor_ definitions.
sum | F(obs) - F(calc) |
R = ------------------------
sum | F(obs) |
F(obs) = the observed structure-factor amplitudes F(calc) = the calculated structure-factor amplitudes
and the sum is taken over the specified reflections
_refine_ls_R_factor_obs
CIF
Residual factor for the reflections classified as 'observed'
(see _reflns_observed_criterion) and included in the refinement. The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. This is the conventional R factor. See also _refine_ls_wR_factor_ definitions.
sum | F(obs) - F(calc) |
R = ------------------------
sum | F(obs) |
F(obs) = the observed structure-factor amplitudes F(calc) = the calculated structure-factor amplitudes
and the sum is taken over the specified reflections
_refine_ls_R_Fsqd_factor
CIF
Residual factor R(Fsqd), calculated on the squared amplitudes
of the observed and calculated structure factors, for
significantly intense reflections (satisfying
_reflns_threshold_expression) and included in the refinement.
The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low.
sum | F(obs)^2^ - F(calc)^2^ |
R(Fsqd) = -------------------------------
sum F(obs)^2^
F(obs)^2^ = squares of the observed structure-factor amplitudes
F(calc)^2^ = squares of the calculated structure-factor
amplitudes
and the sum is taken over the specified reflections
_refine_ls_R_I_factor
CIF
Residual factor R(I) for significantly intense reflections
(satisfying _reflns_threshold_expression) and included in
the refinement.
This is most often calculated in Rietveld refinements against powder data, where it is referred to as R~B~ or R~Bragg~.
sum | I(obs) - I(calc) |
R(I) = ------------------------
sum | I(obs) |
I(obs) = the net observed intensities I(calc) = the net calculated intensities
and the sum is taken over the specified reflections
_refine_ls_restrained_S_all
CIF
The least-squares goodness-of-fit parameter S' for all
reflections after the final cycle of least-squares refinement. This parameter explicitly includes the restraints applied in the least-squares process. See also _refine_ls_goodness_of_fit_ definitions.
{sum { w [ Y(obs) - Y(calc) ]^2^ } }^1/2^
{ + sum~r~ { w~r~ [ P(calc) - P(targ) ]^2^ } }
S' = { -------------------------------------------------- }
{ N~ref~ + N~restr~ - N~param~ }
Y(obs) = the observed coefficients
(see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients
(see _refine_ls_structure_factor_coef)
w = the least-squares reflection weight
[1/square of standard uncertainty (e.s.d.)]
P(calc) = the calculated restraint values P(targ) = the target restraint values w~r~ = the restraint weight
N~ref~ = the number of reflections used in the refinement
(see _refine_ls_number_reflns)
N~restr~ = the number of restraints
(see _refine_ls_number_restraints)
N~param~ = the number of refined parameters
(see _refine_ls_number_parameters)
sum is taken over the specified reflections sum~r~ is taken over the restraints
_refine_ls_restrained_S_gt
CIF
The least-squares goodness-of-fit parameter S' for
significantly intense reflections (satisfying
_reflns_threshold_expression) after the final cycle
of least-squares refinement. This parameter explicitly includes
the restraints applied in the least-squares process.
See also _refine_ls_goodness_of_fit_ definitions.
{sum { w [ Y(obs) - Y(calc) ]^2^ } }^1/2^
{ + sum~r~ { w~r~ [ P(calc) - P(targ) ]^2^ } }
S' = { -------------------------------------------------- }
{ N~ref~ + N~restr~ - N~param~ }
Y(obs) = the observed coefficients
(see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients
(see _refine_ls_structure_factor_coef)
w = the least-squares reflection weight
[1/square of standard uncertainty (e.s.d.)]
P(calc) = the calculated restraint values P(targ) = the target restraint values w~r~ = the restraint weight
N~ref~ = the number of reflections used in the refinement
(see _refine_ls_number_reflns)
N~restr~ = the number of restraints
(see _refine_ls_number_restraints)
N~param~ = the number of refined parameters
(see _refine_ls_number_parameters)
sum is taken over the specified reflections sum~r~ is taken over the restraints
_refine_ls_restrained_S_obs
CIF
The least-squares goodness-of-fit parameter S' for observed
reflections after the final cycle of least-squares refinement. This parameter explicitly includes the restraints applied in the least-squares process. See also _refine_ls_goodness_of_fit_ definitions.
{sum { w [ Y(obs) - Y(calc) ]^2^ } }^1/2^
{ + sum~r~ { w~r~ [ P(calc) - P(targ) ]^2^ } }
S' = { -------------------------------------------------- }
{ N~ref~ + N~restr~ - N~param~ }
Y(obs) = the observed coefficients
(see _refine_ls_structure_factor_coef)
Y(calc) = the calculated coefficients
(see _refine_ls_structure_factor_coef)
w = the least-squares reflection weight
[1/square of standard uncertainty (e.s.d.)]
P(calc) = the calculated restraint values P(targ) = the target restraint values w~r~ = the restraint weight
N~ref~ = the number of reflections used in the refinement
(see _refine_ls_number_reflns)
N~restr~ = the number of restraints
(see _refine_ls_number_restraints)
N~param~ = the number of refined parameters
(see _refine_ls_number_parameters)
sum is taken over the specified reflections sum~r~ is taken over the restraints
_refine_ls_shift/esd_max
CIF
The largest ratio of the final least-squares parameter
shift to the final standard uncertainty (s.u., formerly described as estimated standard deviation, e.s.d.).
_refine_ls_shift/esd_mean
CIF
The average ratio of the final least-squares parameter
shift to the final standard uncertainty (s.u., formerly described as estimated standard deviation, e.s.d.).
_refine_ls_shift/su_max
CIF
The largest ratio of the final least-squares parameter
shift to the final standard uncertainty.
_refine_ls_shift/su_max_lt
CIF
An upper limit for the largest ratio of the final
least-squares parameter shift to the final standard uncertainty. This item is used when the largest value of the shift divided by the final standard uncertainty is too small to measure.
_refine_ls_shift/su_mean
CIF
The average ratio of the final least-squares parameter
shift to the final standard uncertainty.
_refine_ls_shift/su_mean_lt
CIF
An upper limit for the average ratio of the final
least-squares parameter shift to the final standard uncertainty. This item is used when the average value of the shift divided by the final standard uncertainty is too small to measure.
_refine_ls_structure_factor_coef
CIF
Structure-factor coefficient |F|, F^2^ or I used in the
least-squares refinement process.
_refine_ls_weighting_details
CIF
A description of special aspects of the weighting scheme used
in the least-squares refinement. Used to describe the weighting
when the value of _refine_ls_weighting_scheme is specified
as 'calc'.
Example:
Sigdel model of Konnert-Hendrickson:
Sigdel = Afsig + Bfsig*(sin(θ)/λ - 1/6)
Afsig = 22.0, Bfsig = 150.0 at the beginning of refinement.
Afsig = 16.0, Bfsig = 60.0 at the end of refinement.
_refine_ls_weighting_scheme
CIF
The weighting scheme applied in the least-squares process. The
standard code may be followed by a description of the weight
(but see _refine_ls_weighting_details for a preferred approach).
_refine_ls_wR_factor_all
CIF
Weighted residual factors for all reflections.
The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also the _refine_ls_R_factor_ definitions.
( sum w [ Y(obs) - Y(calc) ]^2^ )^1/2^
wR = ( ------------------------------ )
( sum w Y(obs)^2^ )
Y(obs) = the observed amplitude specified by
_refine_ls_structure_factor_coef
Y(calc) = the calculated amplitude specified by
_refine_ls_structure_factor_coef
w = the least-squares weight
and the sum is taken over the specified reflections
_refine_ls_wR_factor_gt
CIF
Weighted residual factors for significantly intense reflections
(satisfying _reflns_threshold_expression) included in the refinement. The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also the _refine_ls_R_factor_ definitions.
( sum w [ Y(obs) - Y(calc) ]^2^ )^1/2^
wR = ( ------------------------------ )
( sum w Y(obs)^2^ )
Y(obs) = the observed amplitude specified by
_refine_ls_structure_factor_coef
Y(calc) = the calculated amplitude specified by
_refine_ls_structure_factor_coef
w = the least-squares weight
and the sum is taken over the specified reflections
_refine_ls_wR_factor_obs
CIF
Weighted residual factors for the reflections classified as
'observed' (see _reflns_observed_criterion) and included in the refinement. The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also the _refine_ls_R_factor_ definitions.
( sum w [ Y(obs) - Y(calc) ]^2^ )^1/2^
wR = ( ------------------------------ )
( sum w Y(obs)^2^ )
Y(obs) = the observed amplitude specified by
_refine_ls_structure_factor_coef
Y(calc) = the calculated amplitude specified by
_refine_ls_structure_factor_coef
w = the least-squares weight
and the sum is taken over the specified reflections
_refine_ls_wR_factor_ref
CIF
Weighted residual factors for all reflections included in the
refinement. The reflections also satisfy the resolution limits established by _refine_ls_d_res_high and _refine_ls_d_res_low. See also the _refine_ls_R_factor_ definitions.
( sum w [ Y(obs) - Y(calc) ]^2^ )^1/2^
wR = ( ------------------------------ )
( sum w Y(obs)^2^ )
Y(obs) = the observed amplitude specified by
_refine_ls_structure_factor_coef
Y(calc) = the calculated amplitude specified by
_refine_ls_structure_factor_coef
w = the least-squares weight
and the sum is taken over the specified reflections
_refine_special_details
CIF
Description of special aspects of the refinement process.
_REFINE_LS_CLASS_[]
CIF
Data items in the REFINE_LS_CLASS category record details
(for each reflection class separately) about the reflections used for the structure refinement.
Example:
loop_
_refine_ls_class_R_factor_gt
_refine_ls_class_code
0.057 'Main'
0.074 'Com'
0.064 'NbRefls'
0.046 'LaRefls'
0.112 'Sat1'
0.177 'Sat2'
_refine_ls_class_code
CIF
The code identifying a certain reflection class. This code must
match a _reflns_class_code.
Examples:
1
m1
s2
_refine_ls_class_d_res_high
CIF
For each reflection class, the highest resolution in angstroms
for the reflections used in the refinement. This is the lowest d value in a reflection class.
_refine_ls_class_d_res_low
CIF
For each reflection class, the lowest resolution in angstroms
for the reflections used in the refinement. This is the highest d value in a reflection class.
_refine_ls_class_R_factor
CIF
Data names: _refine_ls_class_R_factor_all _refine_ls_class_R_factor_gt
For each reflection class, the residual factors for all
reflections, and for significantly intense reflections (see _reflns_threshold_expression), included in the refinement. The reflections also satisfy the resolution limits established by _refine_ls_class_d_res_high and _refine_ls_class_d_res_low. This is the conventional R factor.
sum | F(obs) - F(calc) |
R = ------------------------
sum | F(obs) |
F(obs) = the observed structure-factor amplitudes F(calc) = the calculated structure-factor amplitudes
and the sum is taken over the reflections of this class. See also
_refine_ls_class_wR_factor_all definitions.
_refine_ls_class_R_Fsqd_factor
CIF
For each reflection class, the residual factor R(F^2^) calculated
on the squared amplitudes of the observed and calculated
structure factors for the reflections judged significantly
intense (i.e. satisfying the threshold specified by
_reflns_threshold_expression) and included in the refinement.
The reflections also satisfy the resolution limits established by _refine_ls_class_d_res_high and _refine_ls_class_d_res_low.
sum | F(obs)^2^ - F(calc)^2^ |
R(Fsqd) = -------------------------------
sum F(obs)^2^
F(obs)^2^ = squares of the observed structure-factor amplitudes
F(calc)^2^ = squares of the calculated structure-factor
amplitudes
and the sum is taken over the reflections of this class.
_refine_ls_class_R_I_factor
CIF
For each reflection class, the residual factor R(I) for the
reflections judged significantly intense (i.e. satisfying the
threshold specified by _reflns_threshold_expression) and
included in the refinement.
This is most often calculated in Rietveld refinements against powder data, where it is referred to as R~B~ or R~Bragg~.
sum | I(obs) - I(calc) |
R(I) = ------------------------
sum | I(obs) |
I(obs) = the net observed intensities I(calc) = the net calculated intensities
and the sum is taken over the reflections of this class.
_refine_ls_class_wR_factor_all
CIF
For each reflection class, the weighted residual factors for all
reflections included in the refinement. The reflections also satisfy the resolution limits established by _refine_ls_class_d_res_high and _refine_ls_class_d_res_low.
( sum w [ Y(obs) - Y(calc) ]^2^ )^1/2^
wR = ( ------------------------------ )
( sum w Y(obs)^2^ )
Y(obs) = the observed amplitudes specified by
_refine_ls_structure_factor_coef
Y(calc) = the calculated amplitudes specified by
_refine_ls_structure_factor_coef
w = the least-squares weights
and the sum is taken over the reflections of this class. See also _refine_ls_class_R_factor_ definitions.
_REFLN_[]
CIF
Data items in the REFLN category record details about the
reflections used to determine the ATOM_SITE data items.
The REFLN data items refer to individual reflections and must be included in looped lists.
The REFLNS data items specify the parameters that apply to all reflections. The REFLNS data items are not looped.
Examples:
loop_
_refln_index_h
_refln_index_k
_refln_index_l
_refln_F_squared_calc
_refln_F_squared_meas
_refln_F_squared_sigma
_refln_include_status
2 0 0 85.57 58.90 1.45 o
3 0 0 15718.18 15631.06 30.40 o
4 0 0 55613.11 49840.09 61.86 o
5 0 0 246.85 241.86 10.02 o
6 0 0 82.16 69.97 1.93 o
7 0 0 1133.62 947.79 11.78 o
8 0 0 2558.04 2453.33 20.44 o
9 0 0 283.88 393.66 7.79 o
10 0 0 283.70 171.98 4.26 o
loop_
_refln_index_h
_refln_index_k
_refln_index_l
_refln_F_meas
_refln_F_calc
_refln_F_sigma
_refln_include_status
_refln_scale_group_code
0 0 6 34.935 36.034 3.143 o 1
0 0 12 42.599 40.855 2.131 o 1
0 1 0 42.500 42.507 4.719 o 1
0 1 1 59.172 57.976 4.719 o 1
0 1 2 89.694 94.741 4.325 o 1
0 1 3 51.743 52.241 3.850 o 1
0 1 4 9.294 10.318 2.346 o 1
0 1 5 41.160 39.951 3.313 o 1
0 1 6 6.755 7.102 .895 < 1
0 1 7 30.693 31.171 2.668 o 1
0 1 8 12.324 12.085 2.391 o 1
0 1 9 15.348 15.122 2.239 o 1
0 1 10 17.622 19.605 1.997 o 1
_refln_A
CIF
Data names: _refln_A_calc _refln_A_meas
The calculated and measured structure-factor component A
(in electrons for X-ray diffraction).
A =|F|cos(phase)
_refln_B
CIF
Data names: _refln_B_calc _refln_B_meas
The calculated and measured structure-factor component B
(in electrons for X-ray diffraction).
B =|F|sin(phase)
_refln_class_code
CIF
The code identifying the class to which this reflection has been
assigned. This code must match a value of _reflns_class_code.
Reflections may be grouped into classes for a variety of
purposes. For example, for modulated structures each reflection
class may be defined by the number m=sum|m~i~|, where the m~i~
are the integer coefficients that, in addition to h,k,l, index
the corresponding diffraction vector in the basis defined
for the reciprocal lattice.
_refln_crystal_id
CIF
Code identifying each crystal if multiple crystals are used. Is
used to link with _exptl_crystal_id in the _exptl_crystal_ list.
_refln_d_spacing
CIF
The d spacing in angstroms for this reflection. This is related
to the (sin theta)/lambda value by the expression
_refln_d_spacing = 2/(_refln_sint/lambda)
_refln_F
CIF
Data names: _refln_F_calc _refln_F_meas _refln_F_sigma
The calculated, measured and standard uncertainty (derived from
measurement) of the structure factors (in electrons for X-ray diffraction).
_refln_F_squared
CIF
Data names: _refln_F_squared_calc _refln_F_squared_meas _refln_F_squared_sigma
Calculated, measured and estimated standard uncertainty (derived
from measurement) of the squared structure factors (in electrons squared for X-ray diffraction).
_refln_include_status
CIF
Classification of a reflection indicating its status with
respect to inclusion in the refinement and the calculation of R factors.
_refln_index
CIF
Data names: _refln_index_h _refln_index_k _refln_index_l
Miller indices of the reflection. The values of the Miller
indices in the REFLN category must correspond to the cell defined by the cell lengths and cell angles in the CELL category.
_refln_intensity
CIF
Data names: _refln_intensity_calc _refln_intensity_meas _refln_intensity_sigma
The calculated, measured and standard uncertainty (derived from
measurement) of the intensity, all in the same arbitrary units
as _refln_intensity_meas.
_refln_mean_path_length_tbar
CIF
Mean path length in millimetres through the crystal for this
reflection.
_refln_observed_status
CIF
Classification of a reflection indicating its status with
respect to inclusion in the refinement and the calculation of R factors.
_refln_phase_calc
CIF
The calculated structure-factor phase in degrees.
_refln_phase_meas
CIF
The measured structure-factor phase in degrees.
_refln_refinement_status
CIF
Status of a reflection in the structure-refinement process.
_refln_scale_group_code
CIF
Code identifying the structure-factor scale. This code must
correspond to one of the _reflns_scale_group_code values.
Examples:
1
2
3
s1
A
B
c1
c2
c3
_refln_sint/lambda
CIF
The (sin theta)/lambda value in reciprocal angstroms for this
reflection.
_refln_symmetry_epsilon
CIF
The symmetry reinforcement factor corresponding to the number of
times the reflection indices are generated identically from the space-group symmetry operations.
_refln_symmetry_multiplicity
CIF
The number of reflections symmetry-equivalent under the Laue
symmetry to the present reflection. In the Laue symmetry, Friedel opposites (h k l and -h -k -l) are equivalent. Tables of symmetry-equivalent reflections are available in International Tables for Crystallography Volume A (2002), Chapter 10.1.
_refln_wavelength
CIF
The mean wavelength in angstroms of the radiation used to measure
this reflection. This is an important parameter for data collected using energy-dispersive detectors or the Laue method.
_refln_wavelength_id
CIF
Code identifying the wavelength in the _diffrn_radiation_ list.
See _diffrn_radiation_wavelength_id.
_REFLNS_[]
CIF
Data items in the REFLNS category record details about the
reflections used to determine the ATOM_SITE data items.
The REFLN data items refer to individual reflections and must be included in looped lists.
The REFLNS data items specify the parameters that apply to all reflections. The REFLNS data items are not looped.
Example:
_reflns_limit_h_min 0 _reflns_limit_h_max 6 _reflns_limit_k_min 0 _reflns_limit_k_max 17 _reflns_limit_l_min 0 _reflns_limit_l_max 22 _reflns_number_total 1592 _reflns_number_gt 1408 _reflns_threshold_expression 'F > 6.0u(F)' _reflns_d_resolution_high 0.8733 _reflns_d_resolution_low 11.9202
_reflns_d_resolution
CIF
Data names: _reflns_d_resolution_high _reflns_d_resolution_low
The highest and lowest resolution in angstroms for the
reflections. These are the smallest and largest d values.
_reflns_Friedel_coverage
CIF
The proportion of Friedel-related reflections present in
the number of 'independent' reflections specified by
the item _reflns_number_total.
This proportion is calculated as the ratio:
[N(crystal class) - N(Laue symmetry)] / N(Laue symmetry)
where, working from the _diffrn_refln_ list,
N(crystal class) is the number of reflections obtained on averaging under the symmetry of the crystal class N(Laue symmetry) is the number of reflections obtained on averaging under the Laue symmetry.
Examples: (a) For centrosymmetric structures, _reflns_Friedel_coverage is necessarily equal to 0.0 as the crystal class is identical to the Laue symmetry. (b) For whole-sphere data for a crystal in the space group P1, _reflns_Friedel_coverage is equal to 1.0, as no reflection h k l is equivalent to -h -k -l in the crystal class and all Friedel pairs {h k l; -h -k -l} have been measured. (c) For whole-sphere data in space group Pmm2, _reflns_Friedel_coverage will be < 1.0 because although reflections h k l and -h -k -l are not equivalent when h k l indices are nonzero, they are when l=0. (d) For a crystal in the space group Pmm2, measurements of the two inequivalent octants h >= 0, k >=0, l lead to the same value as in (c), whereas measurements of the two equivalent octants h >= 0, k, l >= 0 will lead to a value of zero for _reflns_Friedel_coverage.
_reflns_Friedel_fraction_full
CIF
The number of Friedel pairs measured out to
_diffrn_reflns_theta_full. divided by the number theoretically possible (ignoring reflections in centric projections and systematic absences throughout). In contrast to _reflns_Friedel_coverage this can take values in the full range 0 to 1 for any non-centrosymmetric space group, and so one can see at a glance how completely the Friedel pairs have been measured. For centrosymmetric space groups the value would be 0/0 and so would be given as '.'.
_reflns_Friedel_fraction_max
CIF
The number of Friedel pairs measured out to
_diffrn_reflns_theta_max. divided by the number theoretically possible (ignoring reflections in centric projections and systematic absences throughout). In contrast to _reflns_Friedel_coverage this can take values in the full range 0 to 1 for any non-centrosymmetric space group, and so one can see at a glance how completely the Friedel pairs have been measured. For centrosymmetric space groups the value would be 0/0 and so would be given as '.'.
_reflns_limit
CIF
Data names: _reflns_limit_h_max _reflns_limit_h_min _reflns_limit_k_max _reflns_limit_k_min _reflns_limit_l_max _reflns_limit_l_min
Miller indices limits for the reported reflections. These need
not be the same as the _diffrn_reflns_limit_ values.
_reflns_number_gt
CIF
The number of reflections in the _refln_ list (not the
_diffrn_refln_ list) that are significantly intense, satisfying the criterion specified by _reflns_threshold_expression. This may include Friedel-equivalent reflections (i.e. those which are symmetry-equivalent under the Laue symmetry but inequivalent under the crystal class) according to the nature of the structure and the procedures used. Special characteristics of the reflections included in the _refln_ list should be given in the item _reflns_special_details.
_reflns_number_observed
CIF
The number of 'observed' reflections in the _refln_ list (not
the _diffrn_refln_ list). The observed reflections satisfy the threshold criterion specified by _reflns_threshold_expression (or the deprecated item _reflns_observed_criterion). They may include Friedel-equivalent reflections according to the nature of the structure and the procedures used. Special characteristics of the reflections included in the _refln_ list should be given in the item _reflns_special_details.
_reflns_number_total
CIF
The total number of reflections in the _refln_ list (not the
_diffrn_refln_ list). This may include Friedel-equivalent
reflections (i.e. those which are symmetry-equivalent under the
Laue symmetry but inequivalent under the crystal class)
according to the nature of the structure and the procedures
used. Special characteristics of the reflections included
in the _refln_ list should be given in the item
_reflns_special_details.
_reflns_observed_criterion
CIF
The criterion used to classify a reflection as 'observed'. This
criterion is usually expressed in terms of a sigma(I) or sigma(F) threshold.
Example:
I>2u(I)
_reflns_special_details
CIF
Description of the properties of the reported reflection list
that are not given in other data items. In particular, this should include information about the averaging (or not) of symmetry-equivalent reflections including Friedel pairs.
_reflns_threshold_expression
CIF
The threshold, usually based on multiples of u(I), u(F^2^)
or u(F), that serves to identify significantly intense reflections, the number of which is given by _reflns_number_gt. These reflections are used in the calculation of _refine_ls_R_factor_gt.
Example:
I>2u(I)
_REFLNS_CLASS_[]
CIF
Data items in the REFLNS_CLASS category record details, for
each reflection class, about the reflections used to determine the structural parameters.
Example:
loop_
_reflns_class_number_gt
_reflns_class_code
584 'Main'
226 'Sat1'
50 'Sat2'
_reflns_class_code
CIF
The code identifying a certain reflection class.
Examples:
1
m1
s2
_reflns_class_d_res_high
CIF
For each reflection class, the highest resolution in angstroms
for the reflections used in the refinement. This is the smallest d value.
_reflns_class_d_res_low
CIF
For each reflection class, the lowest resolution in angstroms
for the reflections used in the refinement. This is the largest d value.
_reflns_class_description
CIF
Description of each reflection class.
Examples:
m=1 first order satellites
H0L0 common projection reflections
_reflns_class_number_gt
CIF
For each reflection class, the number of significantly intense
reflections (see _reflns_threshold_expression) in the _refln_ list (not the _diffrn_refln_ list). This may include Friedel- equivalent reflections (i.e. those which are symmetry-equivalent under the Laue symmetry but inequivalent under the crystal class) according to the nature of the structure and the procedures used. Special characteristics of the reflections included in the _refln_ list should be given in the item _reflns_special_details.
_reflns_class_number_total
CIF
For each reflection class, the total number of reflections
in the _refln_ list (not the _diffrn_refln_ list). This may
include Friedel-equivalent reflections (i.e. those which are
symmetry-equivalent under the Laue symmetry but inequivalent
under the crystal class) according to the nature of the
structure and the procedures used. Special characteristics
of the reflections included in the _refln_ list should be given
in the item _reflns_special_details.
_reflns_class_R_factor
CIF
Data names: _reflns_class_R_factor_all _reflns_class_R_factor_gt
For each reflection class, the residual factors for all
reflections, and for significantly intense reflections (see _reflns_threshold_expression), included in the refinement. The reflections also satisfy the resolution limits established by _reflns_class_d_res_high and _reflns_class_d_res_low. This is the conventional R factor.
sum | F(obs) - F(calc) |
R = ------------------------
sum | F(obs) |
F(obs) = the observed structure-factor amplitudes F(calc) = the calculated structure-factor amplitudes
and the sum is taken over the reflections of this class. See also
_reflns_class_wR_factor_all definitions.
_reflns_class_R_Fsqd_factor
CIF
For each reflection class, the residual factor R(F^2^) calculated
on the squared amplitudes of the observed and calculated
structure factors, for the reflections judged significantly
intense (i.e. satisfying the threshold specified by
_reflns_threshold_expression) and included in the refinement.
The reflections also satisfy the resolution limits established by _reflns_class_d_res_high and _reflns_class_d_res_low.
sum | F(obs)^2^ - F(calc)^2^ |
R(Fsqd) = -------------------------------
sum F(obs)^2^
F(obs)^2^ = squares of the observed structure-factor amplitudes
F(calc)^2^ = squares of the calculated structure-factor
amplitudes
and the sum is taken over the reflections of this class.
_reflns_class_R_I_factor
CIF
For each reflection class, the residual factor R(I) for the
reflections judged significantly intense (i.e. satisfying the
threshold specified by _reflns_threshold_expression) and
included in the refinement.
This is most often calculated in Rietveld refinements against powder data, where it is referred to as R~B~ or R~Bragg~.
sum | I(obs) - I(calc) |
R(I) = ------------------------
sum | I(obs) |
I(obs) = the net observed intensities I(calc) = the net calculated intensities
and the sum is taken over the reflections of this class.
_reflns_class_wR_factor_all
CIF
For each reflection class, the weighted residual factors for all
reflections included in the refinement. The reflections also satisfy the resolution limits established by _reflns_class_d_res_high and _reflns_class_d_res_low.
( sum w [ Y(obs) - Y(calc) ]^2^ )^1/2^
wR = ( ------------------------------ )
( sum w Y(obs)^2^ )
Y(obs) = the observed amplitudes specified by
_refine_ls_structure_factor_coef
Y(calc) = the calculated amplitudes specified by
_refine_ls_structure_factor_coef
w = the least-squares weights
and the sum is taken over the reflections of this class. See also _reflns_class_R_factor_ definitions.
_REFLNS_SCALE_[]
CIF
Data items in the REFLNS_SCALE category record details about
the structure-factor scales. They are referenced from within
the REFLN list through _refln_scale_group_code.
Example:
loop_
_reflns_scale_group_code
_reflns_scale_meas_F
1 .895447
2 .912743
_reflns_scale_group_code
CIF
The code identifying a scale _reflns_scale_meas_. These are
linked to the _refln_ list by the _refln_scale_group_code. These
codes need not correspond to those in the _diffrn_scale_ list.
_reflns_scale_meas
CIF
Data names: _reflns_scale_meas_F _reflns_scale_meas_F_squared _reflns_scale_meas_intensity
Scales associated with _reflns_scale_group_code.
_REFLNS_SHELL_[]
CIF
Data items in the REFLNS_SHELL category record details about
the reflections used to determine the ATOM_SITE data items, as broken down by shells of resolution.
Example:
loop_
_reflns_shell_d_res_high
_reflns_shell_d_res_low
_reflns_shell_meanI_over_uI_gt
_reflns_shell_number_measured_gt
_reflns_shell_number_unique_gt
_reflns_shell_percent_possible_gt
_reflns_shell_Rmerge_F_gt
31.38 3.82 69.8 9024 2540 96.8 1.98
3.82 3.03 26.1 7413 2364 95.1 3.85
3.03 2.65 10.5 5640 2123 86.2 6.37
2.65 2.41 6.4 4322 1882 76.8 8.01
2.41 2.23 4.3 3247 1714 70.4 9.86
2.23 2.10 3.1 1140 812 33.3 13.99
_reflns_shell_d_res_high
CIF
The highest resolution in angstroms for the reflections in
this shell. This is the smallest d value.
_reflns_shell_d_res_low
CIF
The lowest resolution in angstroms for the
reflections in this shell. This is the largest d value.
_reflns_shell_meanI_over_sigI_all
CIF
The ratio of the mean of the intensities of all reflections
in this shell to the mean of the standard uncertainties of the intensities of all reflections in the resolution shell.
_reflns_shell_meanI_over_sigI_gt
CIF
The ratio of the mean of the intensities of the significantly
intense reflections (see _reflns_threshold_expression) in
this shell to the mean of the standard uncertainties of the
intensities of the significantly intense reflections in the
resolution shell.
_reflns_shell_meanI_over_sigI_obs
CIF
The ratio of the mean of the intensities of the reflections
classified as 'observed' (see _reflns_observed_criterion) in
this shell to the mean of the standard uncertainties of the
intensities of the 'observed' reflections in the resolution
shell.
_reflns_shell_meanI_over_uI_all
CIF
The ratio of the mean of the intensities of all reflections
in this shell to the mean of the standard uncertainties of the intensities of all reflections in the resolution shell.
_reflns_shell_meanI_over_uI_gt
CIF
The ratio of the mean of the intensities of the significantly
intense reflections (see _reflns_threshold_expression) in
this shell to the mean of the standard uncertainties of the
intensities of the significantly intense reflections in the
resolution shell.
_reflns_shell_number_measured_all
CIF
The total number of reflections measured for this
resolution shell.
_reflns_shell_number_measured_gt
CIF
The number of significantly intense reflections
(see _reflns_threshold_expression) measured for this
resolution shell.
_reflns_shell_number_measured_obs
CIF
The number of reflections classified as 'observed'
(see _reflns_observed_criterion) measured for this
resolution shell.
_reflns_shell_number_possible
CIF
The number of unique reflections it is possible to measure in
this reflection shell.
_reflns_shell_number_unique_all
CIF
The total number of measured reflections resulting from
merging measured symmetry-equivalent reflections for this resolution shell.
_reflns_shell_number_unique_gt
CIF
The total number of significantly intense reflections
(see _reflns_threshold_expression) resulting from merging
measured symmetry-equivalent reflections for this resolution
shell.
_reflns_shell_number_unique_obs
CIF
The total number of reflections classified as
'observed' (see _reflns_observed_criterion) resulting from
merging measured symmetry-equivalent reflections for this
resolution shell.
_reflns_shell_percent_possible_all
CIF
The percentage of geometrically possible reflections
represented by all reflections measured for this resolution shell.
_reflns_shell_percent_possible_gt
CIF
The percentage of geometrically possible reflections
represented by significantly intense reflections
(see _reflns_threshold_expression) measured for this
resolution shell.
_reflns_shell_percent_possible_obs
CIF
The percentage of geometrically possible reflections
represented by reflections classified as 'observed'
(see _reflns_observed_criterion) measured for this
resolution shell.
_reflns_shell_Rmerge_F_all
CIF
The value of Rmerge(F) for all reflections in a given shell.
sum~i~ ( sum~j~ | F~j~ - <F> | )
Rmerge(F) = --------------------------------
sum~i~ ( sum~j~ <F> )
F~j~ = the amplitude of the jth observation of reflection i
<F> = the mean of the amplitudes of all observations of
reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
_reflns_shell_Rmerge_F_gt
CIF
The value of Rmerge(F) for significantly intense reflections
(see _reflns_threshold_expression) in a given shell.
sum~i~ ( sum~j~ | F~j~ - <F> | )
Rmerge(F) = --------------------------------
sum~i~ ( sum~j~ <F> )
F~j~ = the amplitude of the jth observation of reflection i
<F> = the mean of the amplitudes of all observations of
reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
_reflns_shell_Rmerge_F_obs
CIF
The value of Rmerge(F) for reflections classified as 'observed'
(see _reflns_observed_criterion) in a given shell.
sum~i~ ( sum~j~ | F~j~ - <F> | )
Rmerge(F) = --------------------------------
sum~i~ ( sum~j~ <F> )
F~j~ = the amplitude of the jth observation of reflection i
<F> = the mean of the amplitudes of all observations of
reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
_reflns_shell_Rmerge_I_all
CIF
The value of Rmerge(I) for all reflections in a given shell.
sum~i~ ( sum~j~ | I~j~ - <I> | )
Rmerge(I) = --------------------------------
sum~i~ ( sum~j~ <I> )
I~j~ = the intensity of the jth observation of reflection i
<I> = the mean of the intensities of all observations of
reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
_reflns_shell_Rmerge_I_gt
CIF
The value of Rmerge(I) for significantly intense reflections
(see _reflns_threshold_expression) in a given shell.
sum~i~ ( sum~j~ | I~j~ - <I> | )
Rmerge(I) = --------------------------------
sum~i~ ( sum~j~ <I> )
I~j~ = the intensity of the jth observation of reflection i
<I> = the mean of the intensities of all observations of
reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
_reflns_shell_Rmerge_I_obs
CIF
The value of Rmerge(I) for reflections classified as 'observed'
(see _reflns_observed_criterion) in a given shell.
sum~i~ ( sum~j~ | I~j~ - <I> | )
Rmerge(I) = --------------------------------
sum~i~ ( sum~j~ <I> )
I~j~ = the intensity of the jth observation of reflection i
<I> = the mean of the intensities of all observations of
reflection i
sum~i~ is taken over all reflections sum~j~ is taken over all observations of each reflection.
_SPACE_GROUP_[]
CIF
Contains all the data items that refer to the space group as a
whole, such as its name or crystal system. They may be looped, for example, in a list of space groups and their properties.
Only a subset of the SPACE_GROUP category items appear in the core dictionary. The remainder are found in the symmetry CIF dictionary.
Space-group types are identified by their number as given in International Tables for Crystallography Vol. A. Specific settings of the space groups can be identified either by their Hall symbol or by specifying their symmetry operations.
The commonly used Hermann-Mauguin symbol determines the space-group type uniquely but several different Hermann-Mauguin symbols may refer to the same space-group type. A Hermann-Mauguin symbol contains information on the choice of the basis, but not on the choice of origin. Different formats for the Hermann-Mauguin symbol are found in the symmetry CIF dictionary.
Example:
_space_group_id 1 _space_group_name_H-M_alt 'C 2/c' _space_group_IT_number 15 _space_group_name_Hall '-C 2yc' _space_group_crystal_system monoclinic
_space_group_crystal_system
CIF
The name of the system of geometric crystal classes of space
groups (crystal system) to which the space group belongs. Note that rhombohedral space groups belong to the trigonal system.
_space_group_id
CIF
This is an identifier needed if _space_group_ items are looped.
_space_group_IT_number
CIF
The number as assigned in International Tables for
Crystallography Vol. A, specifying the proper affine class (i.e. the orientation-preserving affine class) of space groups (crystallographic space-group type) to which the space group belongs. This number defines the space-group type but not the coordinate system in which it is expressed.
_space_group_name_H-M_alt
CIF
_space_group_name_H-M_alt allows any Hermann-Mauguin symbol
to be given. The way in which this item is used is determined by the user and in general is not intended to be interpreted by computer. It may, for example, be used to give one of the extended Hermann-Mauguin symbols given in Table 4.3.2.1 of International Tables for Crystallography Vol. A (2002) or a Hermann-Mauguin symbol for a conventional or unconventional setting.
Each component of the space-group name is separated by a space or an underscore. The use of a space is strongly recommended. The underscore is only retained because it was used in older files. It should not be used in new CIFs. Subscripts should appear without special symbols. Bars should be given as negative signs before the numbers to which they apply.
The commonly used Hermann-Mauguin symbol determines the space-
group type uniquely but a given space-group type may be
described by more than one Hermann-Mauguin symbol. The space-
group type is best described using _space_group_IT_number.
The Hermann-Mauguin symbol may contain information on the
choice of basis, but not on the choice of origin. To
define the setting uniquely, use _space_group_name_Hall or
list the symmetry operations.
Example:
loop_
_space_group_id
_space_group_name_H-M_alt
1 'C m c m'
2 'C 2/c 2/m 21/m'
3 'A m a m'
_space_group_name_Hall
CIF
Space-group symbol defined by Hall.
Each component of the space-group name is separated by a space or an underscore. The use of a space is strongly recommended. The underscore is only retained because it was used in older files. It should not be used in new CIFs.
_space_group_name_Hall uniquely defines the space group and
its reference to a particular coordinate system.
Ref: Hall, S. R. (1981). Acta Cryst. A37, 517-525; erratum
(1981), A37, 921.
[See also International Tables for Crystallography,
Vol. B (2001), Chapter 1.4, Appendix 1.4.2]
Examples:
P 2c -2ac
-I 4bd 2ab 3
_SPACE_GROUP_SYMOP_[]
CIF
Contains information about the symmetry operations of the
space group.
Example:
loop_
_space_group_symop_id
_space_group_symop_operation_xyz
1 x,y,z
2 -x,-y,-z
3 -x,1/2+y,1/2-z
4 x,1/2-y,1/2+z
_space_group_symop_id
CIF
An arbitrary identifier that uniquely labels each symmetry
operation in the list.
In order for the defaults to work correctly, the identity operation should have _space_group_symop_id or _symmetry_equiv_pos_site_id set to 1, and _space_group_symop_operation_xyz or _symmetry_equiv_pos_as_xyz set to x,y,z; i.e. the operation labelled 1 should be the identity operation.
_space_group_symop_operation_xyz
CIF
A parsable string giving one of the symmetry operations of the
space group in algebraic form. If W is a matrix representation of the rotational part of the symmetry operation defined by the positions and signs of x, y and z, and w is a column of translations defined by fractions, an equivalent position X' is generated from a given position X by the equation
X' = WX + w
(Note: X is used to represent bold_italics_x in International Tables for Crystallography Vol. A, Part 5)
When a list of symmetry operations is given, it must contain a complete set of coordinate representatives which generates all the operations of the space group by the addition of all primitive translations of the space group. Such representatives are to be found as the coordinates of the general-equivalent position in International Tables for Crystallography Vol. A (2002), to which it is necessary to add any centring translations shown above the general-equivalent position.
That is to say, it is necessary to list explicitly all the symmetry operations required to generate all the atoms in the unit cell defined by the setting used.
In order for the defaults to work correctly, the identity operation should have _space_group_symop_id or _symmetry_equiv_pos_site_id set to 1, and _space_group_symop_operation_xyz or _symmetry_equiv_pos_as_xyz set to x,y,z; i.e. the operation labelled 1 should be the identity operation.
Example:
x,1/2-y,1/2+z
_space_group_symop_sg_id
CIF
This must match a particular value of _space_group_id, allowing
the symmetry operation to be identified with a particular space group.
_SYMMETRY_[]
CIF
Data items in the SYMMETRY category record details about the
space-group symmetry.
Example:
_symmetry_cell_setting orthorhombic _symmetry_space_group_name_H-M 'P 21 21 21' _symmetry_space_group_name_Hall 'P 2ac 2ab'
_symmetry_cell_setting
CIF
The cell settings for this space-group symmetry.
_symmetry_Int_Tables_number
CIF
Space-group number from International Tables for Crystallography
Vol. A (2002).
_symmetry_space_group_name_H-M
CIF
Hermann-Mauguin space-group symbol. Note that the Hermann-Mauguin
symbol does not necessarily contain complete information
about the symmetry and the space-group origin. If used, always
supply the FULL symbol from International Tables for
Crystallography Vol. A (2002) and indicate the origin and
the setting if it is not implicit. If there is any doubt
that the equivalent positions can be uniquely deduced from
this symbol, specify the _symmetry_equiv_pos_as_xyz
or *_Hall data items as well. Leave spaces between
symbols referring to different axes.
Examples:
P 1 21/m 1
P 2/n 2/n 2/n (origin at -1)
R -3 2/m
_symmetry_space_group_name_Hall
CIF
Space-group symbol as described by Hall. This symbol gives the
space-group setting explicitly. Leave spaces between the separate components of the symbol.
Ref: Hall, S. R. (1981). Acta Cryst. A37, 517-525; erratum (1981), A37, 921.
Examples:
-P 2ac 2n
-R 3 2"
P 61 2 2 (0 0 -1)
_SYMMETRY_EQUIV_[]
CIF
Data items in the SYMMETRY_EQUIV category list the
symmetry-equivalent positions for the space group.
Examples:
loop_
_symmetry_equiv_pos_as_xyz
+x,+y,+z 1/2-x,-y,1/2+z 1/2+x,1/2-y,-z -x,1/2+y,1/2-z
loop_
_symmetry_equiv_pos_site_id
_symmetry_equiv_pos_as_xyz
1 x,y,z
2 1/2-x,-y,1/2+z
3 1/2+x,1/2-y,-z
4 -x,1/2+y,1/2-z
_symmetry_equiv_pos_as_xyz
CIF
Symmetry-equivalent position in the 'xyz' representation. Except
for the space group P1, these data will be repeated in a loop. The format of the data item is as per International Tables for Crystallography Vol. A. (2002). All equivalent positions should be entered, including those for lattice centring and a centre of symmetry, if present.
In order for the defaults to work correctly, the identity operation should have _space_group_symop_id or _symmetry_equiv_pos_site_id set to 1, and _space_group_symop_operation_xyz or _symmetry_equiv_pos_as_xyz set to x,y,z; i.e. the operation labelled 1 should be the identity operation.
Example:
-y+x,-y,1/3+z
_symmetry_equiv_pos_site_id
CIF
A code identifying each entry in the _symmetry_equiv_pos_as_xyz
list. It is normally the sequence number of the entry in that list, and should be identified with the code 'n' in _geom_*_symmetry_ codes of the form 'n_klm'.
In order for the defaults to work correctly, the identity operation should have _space_group_symop_id or _symmetry_equiv_pos_site_id set to 1, and _space_group_symop_operation_xyz or _symmetry_equiv_pos_as_xyz set to x,y,z; i.e. the operation labelled 1 should be the identity operation.
_VALENCE_PARAM_[]
CIF
Data items in the VALENCE_PARAM category define the
parameters used for calculating bond valences from bond lengths. In addition to the parameters, a pointer is given to the reference (in VALENCE_REF) from which the bond-valence parameters were taken.
Example:
loop_
_valence_param_id
_valence_param_atom_1
_valence_param_atom_1_valence
_valence_param_atom_2
_valence_param_atom_2_valence
_valence_param_Ro
_valence_param_B
_valence_param_ref_id
_valence_param_details
1 Cu 2 O -2 1.679 0.37 a .
2 Cu 2 O -2 1.649 0.37 j .
3 Cu 2 N -3 1.64 0.37 m '2-coordinate N'
4 Cu 2 N -3 1.76 0.37 m '3-coordinate N'
loop_
_valence_ref_id
_valence_ref_reference
a 'Brown & Altermatt (1985), Acta Cryst. B41, 244-247'
j 'Liu & Thorp (1993), Inorg. Chem. 32, 4102-4205'
m 'See, Krause & Strub (1998), Inorg. Chem. 37, 5369-5375'
_valence_param_atom_1
CIF
The element symbol of the first atom forming the bond whose
bond-valence parameters are given in this category.
_valence_param_atom_1_valence
CIF
The valence (formal charge) of the first atom whose
bond-valence parameters are given in this category.
_valence_param_atom_2
CIF
The element symbol of the second atom forming the bond whose
bond-valence parameters are given in this category.
_valence_param_atom_2_valence
CIF
The valence (formal charge) of the second atom whose
bond-valence parameters are given in this category.
_valence_param_B
CIF
The bond-valence parameter B used in the expression
s = exp[(Ro - R)/B]
where s is the valence of a bond of length R.
_valence_param_details
CIF
Details of or comments on the bond-valence parameters.
_valence_param_id
CIF
An identifier for the valence parameters of a bond between
the given atoms.
_valence_param_ref_id
CIF
An identifier which links to the reference to the source
from which the bond-valence parameters are taken. A child
of _valence_ref_id, which it must match.
_valence_param_Ro
CIF
The bond-valence parameter Ro used in the expression
s = exp[(Ro - R)/B]
where s is the valence of a bond of length R.
_VALENCE_REF_[]
CIF
Data items in the VALENCE_REF category list the references
from which the bond-valence parameters have been taken.
_valence_ref_id
CIF
An identifier for items in this category. Parent of
_valence_param_ref_id, which must have the same value.
_valence_ref_reference
CIF
Literature reference from which the valence parameters
identified by _valence_param_id were taken.
Revision history
1991-05-27 Created from CIF Dictionary text. SRH
1991-05-30 Validated with CYCLOPS & CIF ms. SRH
1991-06-03 Adjustments to some definitions. SRH
1991-06-06 Adjustments a la B. McMahon. SRH
1991-06-18 Additions & some redefinitions. SRH
1991-07-04 Corrected 90:0 in *_detect_slit_. SRH
1991-09-20 Additions & some redefinitions. SRH
1991-09-20 Final published version. IUCr
1991-11-12 Add _diffrn_ambient_environment. SRH
1991-11-12 Allow 'c' for _atom_site_calc_flag. SRH
1993-02-23 Apply global_ and 'unknown' -> '?' SRH
1993-03-05 Changes resulting from MM dictionary. SRH
1993-05-20 Changes arising from new DDL commands. SRH
1993-08-05 Additional finetuning pre-Beijing. SRH
1993-12-22 Introductory sections added to categories. BMcM
1993-12-22 Additional categories from mm work: audit_author,
citation, atom_sites_fract_tran_matrix. BMcM
1994-03-01 Add 'undef' to _refine_ls_hydrogen_treatment. BMcM
1994-03-01 Add '_publ_section_exptl_prep' and '*_refinement'. BMcM
1994-03-01 Add 'atom_site_aniso_ratio'. BMcM
1994-04-15 Comments from IDB on draft version for circulation. BMcM
1994-04-15 Added _publ_section_exptl_solution. BMcM
1994-07-14 Added B. H. Toby's suggested _diffrn_radiation_xray_symbol and _diffrn_radiation_xray_target. BMcM
1994-08-05 Revised definition for _diffrn_reflns_number (S.R. Hall). BMcM
1994-08-05 Added _atom_type_scat_length_neutron (B.H. Toby). BMcM
1994-10-13 Reworded _diffrn_standards_ a la S.R. Hall. BMcM
1994-10-13 Added _diffrn_radiation_probe for non-X-ray experiments. BMcM
1995-01-17 Rewording of definition of _chemical_melting_point. BMcM
1995-02-24 Changed text references to e.s.d to 'standard uncertainty'. BMcM
1995-07-08 Added _chemical_formula_iupac. BMcM
1995-07-09 Finally added _symmetry_equiv_pos_id. BMcM
1995-07-09 _units_extension, _units_conversion and _units_description
superseded by _units and _units_detail. Suffixed datanames
retained as separate entries. BMcM
1995-10-23 Added _refine_ls_R_Fsqd_factor and _refine_ls_R_I_factor BMcM
1996-03-25 Correlated with mmCIF release 0.8 BMcM
1996-05-16 Added some extra datanames for use by Acta: _publ_section_synopsis, _publ_section_title_footnote, _publ_author_footnote, _journal_paper_category, and various _journal_index_ categories BMcM
1996-05-20 Added geom_hbond category BMcM
1996-06-10 Datanames with suffixes to indicate units moved to a new
compatibility dictionary cif_compat.dic BMcM
1996-06-10 Embarrassing _units_ stuff removed from geom_hbond BMcM
1996-06-10 _list_mandatory and _list_reference added to _publ_author_
datanames (where _list was given as "both") BMcM
1996-06-10 Added audit_conform category BMcM
1996-06-11 Added audit_link category BMcM
1996-06-11 Reworded _exptl_crystal_F_000 definition BMcM
1996-06-11 Added _atom_site_U_equiv_geom BMcM
1996-06-11 Added publ_body category BMcM
1996-06-27 Added examples for most of the remaining category overviews
BMcM
1996-06-27 Added _journal_language BMcM
1996-06-28 Added area-detector definitions from mmCIF dictionary: _diffrn_measurement_device_details, *_specific and *_type; _diffrn_radiation_detector_details, *_specific, *_type; _diffrn_radiation_source_details, *_power, *_specific, *_target, *_type; reflns_shell category BMcM Added _refine_ls_d_res_high and *_low and changed wording of definitions for R factors to include these. BMcM Added 'h' and 'f' flags to _refln_observed_status. BMcM
1996-07-05 Some typos fixed and examples modified as suggested by
P.Strickland and I.D.Brown. BMcM
1996-07-27 BMcM: Added example for _diffrn_orient_refln_[] from G. Madariaga U~ij~ changed to U^ij^ a la Nomenclature Commission Definition of _diffrn_ambient_environment changed to omit vacuum as a possible default environment Changed definitions of *_site_symmetry_* items to I.D.Brown's suggested wording. Compressed various journal indexing categories into one Changed upper enumeration values for _refln_symmetry_epsilon and _refln_symmetry_multiplicity to 48. Added references to deprecated use of B values. Modified descriptions of phone, fax number conventions _publ_manuscript_incl_ entries reworded for greater clarity and given individual data blocks Added _list_reference to _symmetry_equiv_pos_id and changed _list value to 'both' for *_as_xyz to allow the P1 case Added _atom_site_B_equiv_geom for completeness Modified definitions of _atom_sites_[Cartn,fract]_tran_vector_ Added _units stuff to _chemical_formula_weight_* and _exptl_crystal_density_ items Added *_theta, *_omega to _diffrn_orient_refln_angle_ Added 'q' to enumeration list for _diffrn_refln_scan_mode Reworded definition in _diffrn_scale_group_[] Permitted esd for _refln_phase_meas (necessitates splitting _refln_phase_ datablock in two) Added _type_conditions esd for _reflns_scale_meas_
1996-07-28 BMcM: Added example for refln_scale_[] and second example for _refln_[] from Xtal test data set. Changed references to category names to CAPITALS. Merged CELL and CELL_MEASUREMENT categories. Added _units deg to all angle quantities. Renamed _citation_journal_coden_CAS as _citation_journal_abstract_id_CAS Removed _diffrn_measurement_device_details, *_specific, *_type, _diffrn_radiation_detector_details, *_specific, *_type, _diffrn_radiation_source_power, *_specific, *_target, *_type, pending full analysis of requirements for describing diffraction apparatus. Reworded _exptl_crystal_F_000 definition again
1996-08-03 Reworded _refine_ls_number_reflns definition a la S.R.Hall BMcM
1996-09-10 BMcM: Clarified _diffrn_attenuator_scale definition with help from SRH In _refln_symmetry_multiplicity, changed 'structure-factor value' to 'structure-factor magnitudes' Slight modification to _diffrn_reflns_number to exclude all systematic absences, not just those due to centring Removed footnote markers from example of _publ_section_title_footnote Added new example to SYMMETRY_EQUIV category to explain the use of _symmetry_equiv_pos_id Reworking of DIFFRN_RADIATION and DIFFRN_MEASUREMENT categories and introduction of DIFFRN_DETECTOR and DIFFRN_SOURCE a la I.D.Brown
1996-09-11 Corrected category assignment for _diffrn_standards_ items BMcM
1996-09-12 BMcM: Added _cell_id and _cell_measurement_refln_id Changed the term "id" to "identifier" in definitions Renamed _citation_journal_abstract_id_CAS as _citation_abstract_id_CAS Added _audit_block_code and changed definition of _audit_link_block_code to refer to it
1996-09-18 BMcM: Fine tuning of IDB's new DIFFRN categories: in DIFFRN_DETECTOR changed *_type to *_device and added *_device_type. Moved _diffrn_radiation_detector back to DIFFRN_RADIATION category with expanded definition. Reworded definitions of _diffrn_measurement_device and *_device_type. In DIFFRN_RADIATION changed enumeration range for *_polarisn_norm to -180:180 and added 'as viewed from the specimen' to the definition; also added 'Cu K-L~2,3~' to examples for *_type. Reworded definitions for _diffrn_refln_index and _diffrn_source_target, and changed _type of _diffrn_source_power to "numb". Introduced _diffrn_detector_dtime in the DIFFRN_DETECTOR category and restored _diffrn_radiation_detector_dtime to DIFFRN_RADIATION
1996-09-25 BMcM: Reworded definitions of _atom_site_disorder_assembly and *_group
1996-10-02 BMcM: Changed _symmetry_equiv_pos_id to _symmetry_equiv_pos_site_id in recognition of the technical meaning of 'position' in International Tables Addition of the names of the relevant units to definitions of _atom_type_scat_length_neutron, _exptl_crystal_size_, _geom_hbond_distance_, _refine_ls_d_res_high and *_low, _reflns_shell_d_res_high and *_low; and cosmetic expansion of units listed in the definitions for _diffrn_source_current, *_power and *_voltage Addition of '_related_function conversion' to _atom_site_B_equiv_geom and *_U_equiv_geom and _atom_site_B_iso_or_equiv and *_U_iso_or_equiv Examples for CELL_MEASUREMENT_REFLN and DIFFRN_REFLN from Gotzon Madariaga Renamed _atom_site_U_equiv_geom as _atom_site_U_equiv_geom_mean and likewise for *_B_* to increase the consistency of abbreviations, as suggested by I.D. Brown Added disorder example to the ATOM_SITE category description
1996-10-15 BMcM: Modified description of example for DIFFRN_REFLN Changed _enumeration_range of _atom_site_attached_hydrogens from 0:4 to 0:8 (cf CSD entry with refcode DUTMAG01) (PRE) Added '_enumeration_default cif' to _publ_body_format Changed underscores to spaces in the example for the Hall spacegroup symbol in data_symmetry_[] Deleted extraneous '_' in data_(_)citation_abstract_id_CAS
1996-10-27 BMcM: Changed psiscan to psi-scan at request of SRH
1996-11-05 BMcM: Changed _citation_book_coden_ISBN to _citation_book_id_ISBN, _citation_journal_coden_ASTM to _citation_journal_id_ASTM, _citation_journal_coden_CSD to _citation_journal_id_CSD, _citation_journal_coden_ISSN to _citation_journal_id_ISSN, and _citation_Medline_AN to _citation_database_id_Medline. Also modified description of CODEN in _citation_journal_id_ASTM and _database_journal_ASTM (suggested by PMDF) The phrase 'diffraction data' modified to 'intensities' in several places, some other cosmetic commas and enforcement of consistent lower-case units names (PMDF) Clarification of the definition for _diffrn_radiation_polarisn_norm (PMDF) Added 'constr' to _refine_ls_hydrogen_treatment (SRH) Corrected misassignment of category of _diffrn_radiation_detector_dtime (H.J.Bernstein)
1996-11-06 BMcM: Added "_list yes" to items in the REFLNS_SHELL category (IDB) Added "measured" to definition of _reflns_shell_number_unique_all Changed enumeration range for _diffrn_standards_decay_% to ":100" and added statement about negative values (PMDF/SRH)
1996-11-08 BMcM: _diffrn_radiation_detector, _diffrn_radiation_detector_dtime and _diffrn_radiation_source removed (these will be transferred to cif_compat.dic for compatibility with files conforming to the original dictionary) _diffrn_radiation_wavelength_* items moved to new category
1996-11-12 BMcM: Deleted _cell_id and _cell_measurement_refln_id, and clarified the intent of the CELL category in _cell_[] (PMDF) Some small rewordings of various _diffrn_* items due to B.H.Toby
1996-11-14 BMcM: Imposed consistency on the nomenclature of diffraction device data names: _diffrn_detector_device_type -> *_detector_type, _diffrn_measurement_device_details -> *_measurement_details, *_measurement_device_type -> *_measurement_type; introduction of _diffrn_source_device and parallel definitions. Existing *_measurement_details example moved to *_special_details (PMDF)
1996-11-21 BMcM: Reintroduced _diffrn_measurement_device_details, further tidying of data names thus: _diffrn_measurement_type -> *_device_type; _diffrn_detector_device and _diffrn_source_device both drop "_device" (PMDF) Added _journal_data_validation_number and _publ_requested_category to enable handling of CIF-access submissions by Acta Cryst. C
1996-11-23 A few typos fixed. BMcM
1996-11-24 BMcM: Added 'gaussian', 'multi-scan' and 'numerical' to enumeration list for _exptl_absorpt_correction_type (SRH) Added 'mixed' to enumeration list for _refine_ls_hydrogen_treatment (SRH)
1996-11-25 A few typos fixed (BMcM)
1996-11-27 BMcM: Removed looped _related_item from _publ_contact_author and reintroduced _diffrn_radiation_detector, *_dtime and _diffrn_radiation_source (see 1996-11-08) with "_related_function replace" as a preparation for using this mechanism further in version 2.1.
1996-11-27 Release version 2.0. IUCr
1997-01-20 BMcM: Some small changes thanks to PMDF. Double space after period at end of sentence changed to single space throughout; _citation_database_id_Medline _diffrn_detector_type moved to correct alphabetic sequence; space introduced between sentences in definition of _citation_journal_id_CSD; some other minor grammatical changes
1997-10-30 BMcM: (changes to align with Acta C Notes for Authors) Obsoleted *_obs_* entries in REFLNS and REFINE_LS categories and replaced with *_gt_*; obsoleted _refine_ls_shift/esd_ by _refine_ls_shift/su_; obsoleted _atom_site_thermal_displace_type by *_adp_type
1997-11-05 BMcM: (changes to align with Acta C Notes for Authors) Added _diffrn_detector_area_resol_mean, _diffrn_measured_fraction_theta_max and *_full, _diffrn_reflns_theta_full
1997-11-05 BMcM: Added _reflns_number_Friedel; changed various *_obs
items in examples to *_gt equivalents and likewise for
other obsoleted items
1997-11-24 BMcM: Slightly changed wording of _reflns_number_Friedel and _reflns_threshold_expression at suggestion of I.D.Brown. Modified definition of _refine_ls_abs_structure_Flack and changed the text of the example in category REFINE at the request of H.D.Flack.
1997-12-08 BMcM: Removed the phrase "(enantiomorph or polarity)" from _refine_ls_abs_structure_Flack and *_Rogers because "absolute structure" is a phrase uniquely defined (H.D.Flack)
1997-12-08 BMcM: Several instances of \s changed to u
1997-12-08 BMcM: Modified definitions of _reflns_number_total and *_Friedel (after H.D.Flack) to clarify the distinction between crystal-class and Laue-symmetry independent reflection sets
1997-12-08 BMcM: Added _chemical_absolute_configuration and _chemical_optical_rotation (H.D.Flack)
1998-08-04 BMcM: Moved _diffrn_pressure_history and _diffrn_thermal_history from draft msCIF dictionary to core as _exptl_crystal_pressure_history and _exptl_crystal_thermal_history (G. Madariaga/I.D.Brown) Moved _diffrn_symmetry_description and REFINE_LS_CLASS from draft msCIF dictionary to core (G. Madariaga/I.D.Brown)
1998-08-04 BMcM: Minor rewordings of _refine_ls_R_Fsqd_factor, _refine_ls_R_I_factor, various definitions referring to F_calc in electrons, and _reflns_shell_number_unique_* (I.D.Brown)
1998-08-04 BMcM: added _reflns_Friedel_coverage (H.D.Flack/S.R.Hall)
1998-08-04 BMcM: changed formula for F(000) (from
F(000) = [ sum (f~r~^2^ + f~i~^2^) ]^1/2^ to
F(000) = [ (sum f~r~)^2^ + (sum f~i~)^2^ ]^1/2^ ) (H.D.Flack)
1998-08-04 BMcM: added 'syn' and 'unk' as enumerations to _chemical_absolute_configuration (H.D.Flack/A.Linden)
1998-09-02 BMcM: added _exptl_crystal_size_length and modified slightly the definition of _exptl_crystal_size_ (W.Clegg/I.D.Brown) Added _diffrn_attenuator_material (I.D.Brown) Added sentence explaining the physical meaning of the _enumeration_range to _refine_ls_abs_structure_Flack (H.D.Flack) Some rewording in _chemical_absolute_configuration implying that for absolute configuration determination the measurement and reporting of the optical rotation in solution are considered mandatory. (H.D.Flack) Some rewording in _reflns_number_total and *_gt to clarify the inclusion of Friedel reflections; addition of _reflns_Friedel_coverage; deletion of _reflns_number_Friedel (H.D.Flack/S.R.Hall) Further minor rewording to _reflns_shell_number_unique_all, *_gt, *_obs (H.D.Flack)
1998-09-10 BMcM: transferred _diffrn_reflns_number_of_classes and the categories DIFFRN_REFLNS_CLASS, REFLNS_CLASS and REFLNS_SHELL_CLASS from the draft msCIF dictionary; added _diffrn_refln_class_code and _refln_class_code to link individual reflections to their related categories.
1998-12-08 BMcM: implemented H.D. Flack's reworking of DIFFRN_REFLNS_CLASS,
REFLNS_CLASS, REFLNS_SHELL_CLASS and REFINE_LS_CLASS, deleting
the latter two; removed _diffrn_reflns_number_of_classes.
1998-12-15 BMcM: completed the above reworking; fixed embarrassing typo for
_related_function
1999-01-16 BMcM: coreDMG review of version 2.1beta5. Numerous small changes from I.D.Brown, the most significant being: _atom_site_occupancy definition clarifies how to impose an experimental uncertainty on the _enumeration_range; _atom_site_U_iso_or_equiv enumeration range set to infinity; _atom_type_analytical_mass_% enumeration range set as 0:100; expanded definitions of _diffrn_radiation_probe and *_type to clarify the distinction between these two items; added reference to _exptl_crystal_size to the definition of _exptl_crystal_description, and modified the definition of _exptl_crystal_face_diffr_ ; new data item _refln_d_spacing; clarified the role of _reflns_special_details in specifying whether Friedel pairs have been averaged; Numerous small changes from H.D.Flack, most significantly: removed enumeration range from _diffrn_refln_counts_ because *_net can go negative; fixed various typos in equations for wR and S; removed reference to Friedel reflections from _refln_symmetry_multiplicity
1999-01-24 BMcM: further revision to wording of _refln_symmetry_multiplicity following discussions by HDF and IDB Numerous small changes from G.Madariaga, most significantly: a instead of A for real-space cell lengths (_atom_site_B_iso_or_equiv and _atom_site_U_iso_or_equiv); _related_function alternate for _atom_site_Cartn_ & _fract_; "or scattering lengths" added to _atom_type_scat_source; deleted incorrect _list_reference in DIFFRN_RADIATION; added rtf to enumeration in _publ_body_format; added enumeration range to _refine_ls_abs_structure_Rogers
1999-02-04 BMcM: fixed some long lines
1999-02-06 BMcM: data names using sigma as an indicator of experimental standard uncertainty replaced by equivalents using the preferred 'u' notation (HDF): _diffrn_refln_intensity_sigma _diffrn_reflns_av_sigmaI/netI _diffrn_reflns_class_av_sgI/I _diffrn_standards_scale_sigma _reflns_shell_meanI_over_sigI_all _reflns_shell_meanI_over_sigI_gt (_reflns_shell_meanI_over_sigI_obs already replaced by *_gt) addition of '_related function alternate' to new data items corresponding to old items with '_related_function replace' (SRH) Example for _citation_journal_id_CSD changed to 0070 to reflect current practice at PDB (F.C.Bernstein) Added _atom_type_scat_dispersion_source (GM)
1999-03-24 Some minor cosmetic modifications (BMcM)
1999-03-24 Release version 2.1. IUCr
2001-01-09 BMcM: simplified entry for _chemical_absolute_configuration (H.D.Flack) Added _geom_bond_valence and the new categories VALENCE_PARAM and VALENCE_REF (I.D.Brown)
2001-01-11 BMcM: Categories EI, EO, EM added to _publ_requested_category
2001-01-11 Release version 2.2. IUCr
2003-09-28 BMcM: incorporated changes approved by COMCIFS following discussions of the core Dictionary Management Group: _atom_site_fract_ nonsense enumeration default value removed _atom_site_refinement_flags deprecated in favour of new *_flags_posn, *_adp and *_occupancy items _atom_sites_special_details added _cell_reciprocal_angle_ and *_length_ added '_type_conditions esd' added to _chemical_melting_point _chemical_melting_point_gt and *_lt added Added several new items describing chemical properties to the CHEMICAL category: _chemical_properties_biological and *_physical, _chemical_temperature_decomposition_* and *_sublimation_*, at the request of CCDC _citation_database_id_CSD added at request of CCDC Several additional tags storing deposition numbers of database entries and record revision history at request of CCDC: _database_code_depnum_ccdc_fiz, *_journal, *_archive and _database_CSD_history Added _diffrn_ambient_pressure_gt,lt and *_temperature_gt,lt Added _diffrn_source_take-off_angle Added _diffrn_standards_decay_%_lt _diffrn_reflns_measured_fraction_resolution_full and *_max introduced as replacements for _diffrn_measured_fraction_theta_full and *_max, moved to a more appropriate category and defined in terms of resolution rather than angle which depends on the radiation used. Likewise for _diffrn_reflns_resolution_full and *_max as replacements for _diffrn_reflns_theta_full and *_max More specific parsable tags for crystal colour introduced as _exptl_crystal_colour_primary, *_modifier and *_lustre Added _exptl_crystal_density_meas_gt,lt and *_meas_temp_gt,lt Added _exptl_crystal_recrystallization_method Added _publ_contact_author_id_iucr and _publ_author_id_iucr to allow unique author identification by IUCr database reference identifier More datanames for recording imprecise quantities: _refine_ls_shift/su_max_lt and _refine_ls_shift/su_mean_lt Added the categories SPACE_GROUP and SPACE_GROUP_SYMOP as imports from the symmetry dictionary cif_sym.dic Added _related_function 'replace' to a number of items in the old SYMMETRY category pointing to the preferred items from the new SPACE_GROUP category
2003-08-19 BMcM: formal approval for COMCIFS for the additions and
contingent changes discussed on the coreDMG discussion
list from June 2002
2003-09-29 BMcM: second round of changes from coreDMG discussions: Added _enumeration_range to new _chemical_temperature_* items; Expanded definition of _space_group_symop_operation_xyz to make explicit the need for inclusion of centring translations (HDF/IDB) Removed _diffrn_reflns_measured_fraction_resolution_full and *_max for reconsideration following suggestion by Curt Haltiwanger that terms are needed that do not refer to resolution or theta Likewise removed _diffrn_standards_decay_%_lt for further consideration, and added _type_conditions esd to _diffrn_standards_decay_% as a measurable quantity (CH/HDF) Modified _example_detail for _space_group_symop_operation_xyz to use a full and unambiguous wording in accordance with International Tables A (CH/IDB/HDF)
2003-09-29 Removed "_type_conditions esd" from the remaining *_gt and
*_lt items at the suggestion of Gotzon Madariaga:
since these are ceiling/floor values a measurable
uncertainty is pointless (BMcM)
2003-10-01 Fixed some typos following checking by IDB (BMcM)
2003-10-03 BMcM: Final editorial pass. Added _related_function alternate to _exptl_crystal_colour. Also added this flag to the new items which replace existing ones: _atom_site_refinement_flags_* and the _space_group_ items
2003-10-04 Release version 2.3. IUCr
2004-06-06 BMcM: minor editorial changes for International Tables Volume G.
Text of _atom_sites_*_tran_* definitions changed to
ATOM_SITE from STOM_SITES.
Some realignment of examples to fit column width.
2004-09-11 BMcM: corrected related item error in _atom_site_refinement_flags_posn, *_adp and *_occupancy
2004-11-26 NJA: updated reference to IT Vol A from 1987 to 2002
2004-12-22 NJA: minor corrections to hyphenation, spelling and punctuation atom_site definition: ', and so on' removed _atom_site_aniso_B_: 1/4 in formula replaced by (1/4) _atom_site_aniso_label: '...atom coordinate list' changed to '...atom in the atom coordinate list' _atom_site_B_iso_or_equiv: 'anisotropic temperature factor parameters' changed to 'anisotropic displacement components' _atom_site_label: 'Each label may have...' changed to 'Different labels may have...' _atom_site_type_symbol: '...atom specie(s)...' changed to 'atom species (singular or plural)...' _atom_type_scat_Cromer_Mann_: reference to Volume C updated to 2004 _atom_type_symbol: 'atom specie(s)' changed to 'atom species (singular or plural)' _audit_conform_dict_location: 'where the conformant dictionary resides' changed to 'for the dictionary to which the current data block conforms' _audit_conform_dict_version: 'conformant dictionary' changed to 'dictionary to which the current data block conforms'
2004-12-23 NJA: minor corrections to hyphenation, spelling and punctuation _audit_contact_author_fax,_audit_contact_author_phone: edited slightly _cell_angle_: 'in degrees of the reported structure' changed to 'of the reported structure in degrees' _cell_measurement_pressure: 'pressure used to synthesize the sample' changed to 'pressure at which the sample was synthesized' _cell_measurement_theta_: 'angles in degrees of reflections used to measure the unit cell' changed to 'angles of reflections used to measure the unit cell in degrees' _cell_reciprocal_angle_: 'angles in degrees defining the reciprocal cell' changed to 'angles defining the reciprocal cell in degrees' _chemical_[]: 'compounds' changed to 'compound' _chemical_optical_rotation: 'c is the value of CONC in g' changed to 'c is the value of CONC as defined above'. _chemical_properties_physical, _biological: 'free description' changed to 'free-text description' _chemical_conn_atom_display_: 'if absent...staff.' deleted _citation_[]: 'literature cited relevant' changed to 'literature cited as being relevant' _citation_*: 'book chapters' changed to 'books or book chapters' _citation_country: 'both journal articles and' deleted _citation_database_id_CSD: 'containing' changed to 'that contains' _citation_language: 'citation appears' changed to 'cited article is written' _diffrn_crystal_treatment: 'intensity measurement' changed to 'the intensity measurements' _diffrn_special_details: 'diffraction measurement' changed to 'intensity-measurement' _diffrn_attenuator_scale: 'This scale must be multiplied by the measured intensity to convert it...' changed to 'The measured intensity must be multiplied by this scale to convert it...' _diffrn_orient_matrix_[]: 'used in data measurement' changed to 'used in the measurement of the diffraction intensities' _diffrn_orient_refln_angle_: 'in degrees of a reflection... matrix' changed to 'of a reflection...matrix in degrees' _diffrn_radiation_probe,_diffrn_radiation_type: definitions reworded slightly _diffrn_refln_angle_: 'in degrees of a reflection' changed to 'of a reflection in degrees' _diffrn_refln_elapsed_time: 'diffraction measurement' changed to 'the diffraction experiment' _diffrn_refln_scale_group_code: 'applying' changed to 'applicable' _diffrn_refln_scan_mode: 'with a diffractometer' changed to 'for measurements using a diffractometer' _diffrn_refln_scan_rate: 'to measure the intensity in degrees per minute' changed to 'in degrees per minute to measure the intensity' _diffrn_refln_standard_code: 'identifying' changed to 'indicating'; 'intensity' changed to 'reflection' _diffrn_reflns_class_d_res_high,_low: defintions rephrased. _diffrn_source_details: 'used' deleted. _diffrn_source_target: 'for generation of' changed to 'to generate' _diffrn_standards_decay_%: 'at the start of the measurement process and at the finish' changed to 'from the start of the measurement process to the end' _diffrn_standards_number: 'used in the diffraction measurements' changed to 'used during the measurement of the diffraction intensities' _exptl_absorpt_correction_type: 'no more detailed information is' changed to 'more detailed information is not'. _exptl_crystal_[]: 'and so on' deleted _exptl_crystal_face_perp_dist: 'millimetres of the face' changed to 'millimetres from the face' _geom_[], _geom_angle_[], _geom_bond_[], _geom_contact_[], _geom_hbond_[], _geom_torsion_[]: 'contents of the' deleted _geom_contact_[], _geom_torsion_[]: year for reference for example 1 corrected from 1991 to 1992 _geom_hbond_angle_DHA: 'Site at *_D' changed to 'Site at *_H' _publ_contact_author_fax: definition rephrased slightly _publ_requested_category: Cif-access codes marked as '(no longer in use)'
2005-01-05 NJA: minor corrections to hyphenation, spelling and punctuation _refine_ls_*: 'least squares' changed to 'least-squares refinement' _refine_ls_restrained_S_all: `Y(calc) = the observed coefficients` changed to `Y(calc) = the calculated coefficients` _refine_ls_restrained_S_gt: `Y(calc) = the observed coefficients` changed to `Y(calc) = the calculated coefficients` _refine_ls_restrained_S_obs: `Y(calc) = the observed coefficients` changed to `Y(calc) = the calculated coefficients` _refine_ls_shift/esd_*: 'divided by' changed to 'to' _refine_ls_shift/su_*: 'divided by' changed to 'to' _refine_ls_class_d_res_*: edited slightly _refine_ls_d_res_*: edited slightly _refln_intensity_*: edited slightly _refln_symmetry_multiplicity: reference to Volume A updated to (2002), Chapter 10.1 _reflns_d_resolution_*: edited slightly _reflns_class_d_res_*: edited slightly _reflns_shell_d_res_*: edited slightly _space_group_name_Hall: erratum added to reference to Hall (1981); reference to Volume B updated to 2001. _space_group_name_H-M_alt: reference to Volume A updated to (2002) _symmetry_Int_Tables_number: reference to Volume A updated to (2002) _symmetry_space_group_name_Hall: erratum added to reference to Hall (1981) _symmetry_space_group_name_H-M: reference to Volume A updated to (2002) _symmetry_equiv_pos_as_xyz: reference to Volume A updated to (2002)
2005-01-11 NJA: more minor corrections to hyphenation, spelling and
punctuation
2005-01-21 NJA: _reflns_shell_Rmerge_I_obs: related item changed from _reflns_shell_Rmerge_I_obs to _reflns_shell_Rmerge_I_gt
2005-06-21 NJA: corrections to proofs of Intl Tables G Chapter 4.1 included. New data name _publ_author_email added.
2005-06-27 BMcM: Removed _list_mandatory yes from _atom_site_aniso_label in response to cif-developers list discussion
2007-03-27 BMcM: Added _publ_section_related_literature; added new categories (QI, QM, QO) to _publ_requested_category
2007-12-04 BMcM: Fixed typo in equation appearing in _diffrn_reflns_av_sigmaI/netI and _diffrn_reflns_av_unetI/netI
2007-12-04 IDB: Added new items approved by coreDMG: SUMMARY 1. _atom_sites_solution_ Added new flags notdet, dual, other (Bruce Noll) 2. _chemical_enantioexcess_ Added items *_bulk, *_bulk_technique, *_crystal, *_crystal_technique (H. D. Flack) 3. _diffrn_..._measured_fraction_ Added sentences to definitions of _diffrn_reflns_resolution_full, *_theta_max and *_resolution_max. Added new data items _diffrn_reflns_Laue_measured_fraction_full, *_max _diffrn_reflns_point_group_measured_fraction_full and *_max 4. _diffrn_standards_decay_% Clarified definition and added examples. 5. _distributed_density_ Added _atom_site_distributed_density_id and the new DISTRIBUTED_DENSITY category following suggestions from David Watkin. 6. _exptl_absorpt_correction_T_max, *_T_min Clarified definition and added items _exptl_transmission_factor_max and *_min 7. _geom_bond_multiplicity New data item added. 8. _publ_section_keywords New data name added. 9. _refine_ls_F_calc Added _refine_ls_F_calc_details, *_formula and *_precision. 10. _symmetry_equiv Added _enumeration_default 1 to _space_group_symop_id and _symmetry_equiv_pos_site_id; added _enumeration_default x,y,z to _symmetry_equiv_pos_as_xyz; added comment about the need to have the identity as symop 1 to _space_group_symop_operation_xyz, _space_group_symop_id, _symmetry_equiv_pos_as_xyz and _symmetry_equiv_pos_site_id
2008-02-10 BMcM: Final changes after COMCIFS review: Alphabetization of _atom_sites_Cartn_transform_axes, _citation_journal_full and a few others Removed upper enumeration limit from _diffrn_reflns_Laue_measured_fraction_full Fixed typo in definition of _distributed_density_[]. Added comments from GM, IDB, RWGK querying aspects of some other definitions in the proposed DISTRIBUTED_DENSITY category. Removed DISTRIBUTED_DENSITY category for further review. Also removed data_atom_site_distributed_density_id
2010-06-29 BMcM: Added _diffrn_radiation_wavelength_determination
2011-04-26 BMcM: New enumeration value (iterative) for _atom_sites_solution_ (suggested by A. van der Lee) New enumeration value (mixed) for _atom_sites_solution_hydrogens (D. Watkin) Added _journal_paper_doi, _database_code_COD (S. Grazulis), _chemical_identifier_inchi, _chemical_identifier_inchi_key, _chemical_identifier_inchi_version and _diffrn_radiation_wavelength_details
2012-05-16 BMcM: Deprecated _atom_site_symmetry_multiplicity; replaced with _atom_site_site_symmetry_multiplicity and added _atom_site_site_symmetry_order (IDB) Reworded _exptl_crystal_F_000 definition to take account of neutron diffraction and removed _enumeration_range (can be negative for neutrons) Added '_type_conditions su' to _diffrn_radiation_wavelength
2012-11-05 BMcM: Added _reflns_Friedel_fraction_full and _reflns_Friedel_fraction_max Added several new enumeration values to _refine_ls_hydrogen_treatment
2014-05-20 BMcM: Added new categories (GI, GM, GO, Hi, HM, HO) to _publ_requested_category
2014-11-21 BMcM: Data items related to data citation and author identification: _audit_block_doi; _citation_doi; _citation_id; _citation_publisher; _database_dataset_doi; _publ_author_id_orcid; _publ_contact_author_id_orcid
International Tables for Crystallography
Volume G: Definition and exchange of crystallographic data
Edited by S. R. Hall and B. McMahon
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| CIF dictionaries |
An essential guide and reference to CIF for programmers, data managers handling crystal-structure information and practising crystallographers.
