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Approval requested for symmetry dictionary
- To: Multiple recipients of list <[email protected]>
- Subject: Approval requested for symmetry dictionary
- From: Brian McMahon <[email protected]>
- Date: Thu, 31 May 2001 15:49:54 +0100 (BST)
Dear COMCIFS It is my pleasure to bring before you for your approval a new dictionary, cif_sym.dic, containing categories and data names intended to carry detailed information about crystallographic symmetry. If approved, these items are candidates for superseding the existing small symmetry-specific categories in the core dictionary. This dictionary is expressed in a DDL2 formalism to facilitate integration with the core dictionary as embedded in mmCIF; upon approval a DDL1 version will be derived from this suitable for mating with the DDL1 core. This dictionary has been developed under the active supervision of David Brown, and has already passed through several cycles of revision under the eyes of the COMCIFS Dictionary Review Committee. Please review this dictionary and indicate your approval or reservations before the end of June. The dictionary accompanies this mail as an attachment and will also be accessible from 1 June at the URL http://www.iucr.org/iucr-top/cif/sym/cif_sym_0.9.dic Regards Brian _______________________________________________________________________________ Brian McMahon tel: +44 1244 342878 Research and Development Officer fax: +44 1244 314888 International Union of Crystallography e-mail: [email protected] 5 Abbey Square, Chester CH1 2HU, England [email protected]
##########################################################
#
# SYMMETRY CIF DICTIONARY
#
##########################################################
#
# This dictionary is designed to provide the data names
# required to describe crystallographic symmetry.
#
# It is written in DDL2
#
# This version, 0.09, is dated 2001-05-31
#
# The categories and items defined in this version are:
#
# space_group (General information on the space group)
# Bravais_type
# centring_type
# crystal_system
# id (Parent to various .sg_id's)
# Laue_class
# IT_coordinate_system_code
# IT_ number
# name_Hall
# name_H-M
# name_H-M_alt
# name_H-M_alt_description
# name_H-M_full
# name_Schoenflies
# Patterson_name_H-M
# point_group_H-M
# reference_setting
# transform_rotation_xyz
# transform_origin_shift
# space_group_symop (Symmetry operators)
# id (parent to various .symop_id's)
# generator_xyz
# operation_description
# operation_xyz
# sg_id
# space_group_Wyckoff (Details of the Wyckoff positions)
# coords_xyz
# id (parent to various .wyckoff_id's to be defined)
# letter
# multiplicity
# sg_id
# site_symmetry
#
##########################################################
data_cif_sym.dic
_dictionary.title 'cif symmetry dictionary'
_dictionary.version 0.09
_dictionary.datablock_id cif_sym.dic
################################################
#
# CATEGORY: SPACE_GROUP
#
################################################
save_SPACE_GROUP
_category.id space_group
_category.description
; Contains all the data items that refer to the space group as a
whole, such as its name, Laue group etc. It may be looped, for
example, in a list of space groups and their properties.
Space group types are identified by their International Tables
for Crystallography Vol A number or Schoenflies symbol. Specific
settings of the space groups can be identified by their Hall
symbol, by specifying their symmetry operations or generators,
or by giving the transformation that relates the specific setting
to the reference setting based on International Tables for
Crystallography Vol. A and stored in this dictionary.
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. It contains
information on the choice of the basis, but not on the
choice of origin.
;
_category.mandatory_code yes
_category_examples.case
;
_space_group.id 1
_space_group.name_H-M C_2/c
_space_group.name_Schoenflies C2h^6
_space_group.IT_number 15
_space_group.name_Hall -C_2yc
_space_group.Bravais_type mS
_space_group.Laue_class 2/m
_space_group.crystal_system monoclinic
_space_group.centring_type C
_space_group.Patterson_name_H-M C_2/m
;
_category_key.name '_space_group.id'
save_
#############################################
##############################################################################
save__space_group.bravais_type
_item.name '_space_group.bravais_type'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail aP 'triclinic (anorthic) primitive lattice'
_item_description.description
; The symbol denoting the lattice type(Bravais type) to which the
translational subgroup (vector lattice) of the space group
belongs. It consisting of a lower case letter indicating the
crystal system followed by an upper case letter indicating
the lattice centring. The setting-independent symbol mS
replaces the setting-dependent symbols mB and mC, and the
setting-independent symbol oS replaces the setting-dependent
symbols oA, oB and oC (see International Tables for
Crystallography A 1995 edition p.13).
;
_item_type.code char
loop_
_item_enumeration.value
aP
mP mS
oP oS oI oF
tP tI
hP hR
cP cI cF
save_
#---------------------------------------------------
save__space_group.centring_type
_item.name '_space_group.centring_type'
_item.category_id space_group
_item.mandatory_code no
_item_description.description
; Symbol for the lattice centring. This symbol may be dependent
on the coordinate system chosen.
;
_item_type.code char
loop_
_item_enumeration.value
_item_enumeration.detail
P 'primitive no centring'
A 'a face centred (0,1/2,1/2)'
B 'b face centred (1/2,0,1/2)'
C 'c face centred (1/2,1/2,0)'
F 'all faces centred (0,1/2,1/2),(1/2,0,1/2),(1/2,1/2,0)'
I 'body centred (1/2,1/2,1/2)'
R 'rhombohedral obverse centred (2/3,1/3,1/3),(1/3,2/3,2/3)'
Rrev 'rhombohedral reverse centred (1/3,2/3,1/3),(2/3,1/3,2/3)'
H 'hexagonal centred (2/3,1/3,0),(1/3,2/3,0)'
save_
#-----------------------------------------
save__space_group.crystal_system
_item.name '_space_group.crystal_system'
_item.category_id space_group
_item.mandatory_code no
_item_description.description
; The name of the system of geometric crystal classes of space
groups (crystal system) to which the space group belongs.
Note that crystals with the hR lattice type belong to the
trigonal system.
;
_item_type.code char
loop_
_item_enumeration.value
triclinic
monoclinic
orthorhombic
tetragonal
trigonal
hexagonal
cubic
_item_aliases.alias_name '_symmetry_cell_setting'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 1.0
save_
#--------------------------------------------------
save__space_group.id
loop_
_item.name
_item.category_id
_item.mandatory_code
'_space_group.id' space_group yes
'_space_group_symop.sg_id' space_group_symop no
'_space_group_Wyckoff.sg_id' space_group_Wyckoff no
_item_description.description
; This is an identifier needed if _space_group_* items are looped.
;
_item_type.code char
loop_
_item_linked.child_name
_item_linked.parent_name
'_space_group_symop.sg_id' '_space_group.id'
'_space_group_Wyckoff.sg_id' '_space_group.id'
save_
#------------------------------------------------
save__space_group.IT_coordinate_system_code
_item.name '_space_group.IT_coordinate_system_code'
_item.category_id space_group
_item.mandatory_code no
_item_description.description
; A qualifier taken from the enumeration list identifying which
setting in International Tables for Crystallography (3rd Edn)
Vol. A (IT) is used. See IT Table 4.3.1 Section 2.16,
Table 2.16.1 Section 2.16.(i) and Fig. 2.6.4. This item is
not computer interpretable and cannot be used to define the
coordinate system. Use _space_group.transform_* instead.
;
_item_type.code char
loop_
_item_enumeration.value
_item_enumeration.detail
'b1' 'monoclinic unique axis b, cell choice 1, abc'
'b2' 'monoclinic unique axis b, cell choice 2, abc'
'b3' 'monoclinic unique axis b, cell choice 3, abc'
'-b1' 'monoclinic unique axis b, cell choice 1, c-ba'
'-b2' 'monoclinic unique axis b, cell choice 2, c-ba'
'-b3' 'monoclinic unique axis b, cell choice 3, c-ba'
'c1' 'monoclinic unique axis c, cell choice 1, abc'
'c2' 'monoclinic unique axis c, cell choice 2, abc'
'c3' 'monoclinic unique axis c, cell choice 3, abc'
'-c1' 'monoclinic unique axis c, cell choice 1, ba-c'
'-c2' 'monoclinic unique axis c, cell choice 2, ba-c'
'-c3' 'monoclinic unique axis c, cell choice 3, ba-c'
'a1' 'monoclinic unique axis a, cell choice 1, abc'
'a2' 'monoclinic unique axis a, cell choice 2, abc'
'a3' 'monoclinic unique axis a, cell choice 3, abc'
'-a1' 'monoclinic unique axis a, cell choice 1, -acb'
'-a2' 'monoclinic unique axis a, cell choice 2, -acb'
'-a3' 'monoclinic unique axis a, cell choice 3, -acb'
'abc' 'orthorhombic'
'ba-c' 'orthorhombic'
'cab' 'orthorhombic'
'-cba' 'orthorhombic'
'bca' 'orthorhombic'
'a-cb' 'orthorhombic'
'1abc' 'orthorhombic origin choice 1'
'1ba-c' 'orthorhombic origin choice 1'
'1cab' 'orthorhombic origin choice 1'
'1-cba' 'orthorhombic origin choice 1'
'1bca' 'orthorhombic origin choice 1'
'1a-cb' 'orthorhombic origin choice 1'
'2abc' 'orthorhombic origin choice 2'
'2ba-c' 'orthorhombic origin choice 2'
'2cab' 'orthorhombic origin choice 2'
'2-cba' 'orthorhombic origin choice 2'
'2bca' 'orthorhombic origin choice 2'
'2a-cb' 'orthorhombic origin choice 2'
'1' 'tetragonal or cubic origin choice 1'
'2' 'tetragonal or cubic origin choice 2'
'h' 'trigonal using hexagonal axes'
'r' 'trigonal using rhombohedral axes'
save_
#----------------------------------------------
save__space_group.IT_number
_item.name '_space_group.IT_number'
_item.category_id space_group
_item.mandatory_code no
_item_description.description
; 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.
;
_item_type.code numb
_item_range.minimum 1
_item_range.maximum 230
_item_aliases.alias_name '_symmetry_Int_Tables_number'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 1.0
save_
#------------------------------------------------
save__space_group.laue_class
_item.name '_space_group.Laue_class'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_enumeration.value
-1
2/m mmm
4/m 4/mmm
-3 -3m
6/m 6/mmm
m-3 m-3m
_item_description.description
; The Hermann-Mauguin symbol of the geometric crystal class of the
point group of the space group where a center of inversion is
added if not already present.
;
_item_type.code char
save_
#-----------------------------------------------
save__space_group.name_hall
_item.name '_space_group.name_Hall'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail 'P 2c -2ac' 'Equivalent to Pca21'
-I_4bd_2ab_3 'Equivalent to Ia3d'
_item_description.description
; Space group symbol defined by Hall (Acta Cryst. (1981) A37,
517-525) (See also International Tables for Crystallography
Vol.B (1993) 1.4 Appendix B). A space or underline separates
rotation symbols referring to different axes.
_space_group.name_Hall uniquely defines the space group and
its reference to a particular coordinate system.
;
_item_type.code char
_item_aliases.alias_name '_symmetry_space_group_name_Hall'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 1.0
save_
#-------------------------------------------------
save__space_group.name_H-M
_item.name '_space_group.name_H-M'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case 'P 21/c'
P21_c
'P m n a'
'P -1'
F_m_-3_m
P_63/m_m_m
_item_description.description
; The Short International Hermann-Mauguin space group symbol as
defined on pp 14ff and given as the first item of each
Space Group Table in Section 7 of International Tables
for Crystallography Vol.A (1983). A space or underline
separates each symbol referring to different axes.
Subscripts should appear without special symbols. Bars
should be given as negative signs before the numbers to which
they apply. The Short International Hermann-Mauguin symbol
determines the space group type uniquely. However, the space
group type is better described using the *.IT_number or
*.name_Schoenflies. The Short International Hermann-Mauguin
symbol contains no information on the choice of basis or
origin. To define the setting uniquely use *.name_Hall, list
the symmetry operations or generators, or give the
transformation that relates the setting to the reference
setting defined in this dictionary under *.reference_setting.
;
_item_type.code char
loop_
_item_related.related_name
_item_related.function_code '_space_group.name_H-M_full' alternate
'_space_group.name_H-M_alt' alternate
_item_aliases.alias_name '_symmetry_space_group_name_H-M'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 1.0
save_
#----------------------------------------------
save__space_group.name_H-M_alt
_item.name '_space_group.name_H-M_alt'
_item.category_id space_group
_item.mandatory_code no
_item_type.code char
loop_
_item_examples.case
_item_examples.detail
;
loop_
_space_group.name_H-M_alt
_space_group.name_H-M_alt_description
C_m_c_m(b_n_n) 'Extended Hermann-Mauguin symbol'
'C 2/c 2/m 21/m' 'Full unconventional Hermann-Mauguin symbol'
;
'two examples for the space group number 63.'
_item_description.description
; *.name_H-M_alt allows for an alternative Hermann-Mauguin symbol
to be given. The way in which this item is used is determined
by the user and should be described in the item
_space_group.name_H-M_alt_description. It may, for example, be
used to give one of the extended Hermann-Mauguin symbols given
in Table 4.3.1 of International Tables for Crystallography
Vol A (1983) or a full Hermann-Mauguin symbol for an
unconventional setting. A space or underline separates each
symbol referring to different axes. 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 the *.IT_number or *.name_Schoenflies.
The Hermann-Mauguin symbol may contain information on the
choice of basis though not on the choice of origin. To
define the setting uniquely use *.name_Hall, list the
symmetry operations or generators, or give the transformation
that relates the setting to the reference setting defined
in this dictionary under *.reference_setting.
;
loop_
_item_related.related_name
_item_related.function_code '_space_group.name_H-M' alternate
'_space_group.name_H-M_full' alternate
_item_aliases.alias_name '_symmetry_space_group_name_H-M_alt'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 1.0
save_
#---------------------------------------------------
save__space_group.name_H-M_alt_description
_item.name '_space_group.name_H-M_alt_description'
_item.category_id space_group
_item.mandatory_code no
_item_description.description
; A free text description of the code appearing in
_space_group.name_H-M_alt
;
_item_type.code char
save_
#--------------------------------------------------
save__space_group.name_H-M_full
_item.name '_space_group.name_H-M_full'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail
'P 21/n 21/m 21/a' 'full symbol for Pnma'
P_21/n_21/m_21/a 'an alternative way of writing Pnma'
_item_description.description
; The Full International Hermann-Mauguin space group symbol as
defined on pp 14ff and given as the second item of the second
line of one of the Space Group Tables of Section 7 of
International Tables for Crystallography Vol. A (1983). A space
or underline separates each symbol referring to different axes.
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 the *.IT_number
or *.name_Schoenflies. The Full International Hermann-Mauguin
symbol contains information about the choice of basis for
monoclinic and orthorhombic space groups but does not give
information about the choice of origin. To define the setting
uniquely use *.name_Hall, list the symmetry operations
or generators, or give the transformation relating
the setting used to the reference setting defined in this
dictionary under *.reference_setting.
;
_item_type.code char
loop_
_item_related.related_name
_item_related.function_code '_space_group.name_H-M' alternate
'_space_group.name_H-M_alt' alternate
_item_aliases.alias_name '_symmetry_space_group_name_H-M_full'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 1.0
save_
#-----------------------------------------------
save__space_group.name_Schoenflies
_item.name '_space_group.name_Schoenflies'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail
'C2h^5' 'Schoenflies symbol for space group 14'
_item_description.description
; The Schoenflies symbol as listed in International Tables for
Crystallography Vol. A denoting the proper affine class (i.e.
orientation preserving affine class) of space groups (space group
type) to which the space group belongs. This symbol defines the
space group type independently of the coordinate system in which
the space group is expressed.
The symbol is given in the form 'Schoenflies point group
symbol' ^ 'superscript'.
;
_item_type.code char
loop_
_item_enumeration.value
C1^1 Ci^1
C2^1 C2^2 C2^3
Cs^1 Cs^2 Cs^3 Cs^4
C2h^1 C2h^2 C2h^3 C2h^4 C2h^5 C2h^6
D2^1 D2^2 D2^3 D2^4 D2^5 D2^6 D2^7 D2^8 D2^9
C2v^1 C2v^2 C2v^3 C2v^4 C2v^5 C2v^6 C2v^7 C2v^8 C2v^9 C2v^10
C2v^11 C2v^12 C2v^13 C2v^14 C2v^15 C2v^16 C2v^17 C2v^18 C2v^19
C2v^20 C2v^21 C2v^22
D2h^1 D2h^2 D2h^3 D2h^4 D2h^5 D2h^6 D2h^7 D2h^8 D2h^9 D2h^10
D2h^11 D2h^12 D2h^13 D2h^14 D2h^15 D2h^16 D2h^17 D2h^18 D2h^19
D2h^20 D2h^21 D2h^22 D2h^23 D2h^24 D2h^25 D2h^26 D2h^27 D2h^28
C4^1 C4^2 C4^3 C4^4 C4^5 C4^6
S4^1 S4^2
C4h^1 C4h^2 C4h^3 C4h^4 C4h^5 C4h^6
D4^1 D4^2 D4^3 D4^4 D4^5 D4^6 D4^7 D4^8 D4^9 D4^10
C4v^1 C4v^2 C4v^3 C4v^4 C4v^5 C4v^6 C4v^7 C4v^8 C4v^9 C4v^10
C4v^11 C4v^12
D2d^1 D2d^2 D2d^3 D2d^4 D2d^5 D2d^6 D2d^7 D2d^8 D2d^9 D2d^10
D2d^11 D2d^12
D4h^1 D4h^2 D4h^3 D4h^4 D4h^5 D4h^6 D4h^7 D4h^8 D4h^9 D4h^10
D4h^11 D4h^12 D4h^13 D4h^14 D4h^15 D4h^16 D4h^17 D4h^18 D4h^19
D4h^20
C3^1 C3^2 C3^3 C3^4
C3i^1 C3i^2
D3^1 D3^2 D3^3 D3^4 D3^5 D3^6 D3^7
C3v^1 C3v^2 C3v^3 C3v^4 C3v^5 C3v^6
D3d^1 D3d^2 D3d^3 D3d^4 D3d^5 D3d^6
C6^1 C6^2 C6^3 C6^4 C6^5 C6^6
C3h^1
C6h^1 C6h^2
D6^1 D6^2 D6^3 D6^4 D6^5 D6^6
C6v^1 C6v^2 C6v^3 C6v^4
D3h^1 D3h^2 D3h^3 D3h^4
D6h^1 D6h^2 D6h^3 D6h^4
T^1 T^2 T^3 T^4 T^5
Th^1 Th^2 Th^3 Th^4 Th^5 Th^6 Th^7
O^1 O^2 O^3 O^4 O^5 O^6 O^7 O^8
Td^1 Td^2 Td^3 Td^4 Td^5 Td^6
Oh^1 Oh^2 Oh^3 Oh^4 Oh^5 Oh^6 Oh^7 Oh^8 Oh^9 Oh^10
save_
#-----------------------------------------------
save__space_group.Patterson_name_H-M
_item.name '_space_group.Patterson_name_H-M'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case
'P -1'
'P 2/m' 'C 2/m'
'P m m m' 'C m m m' 'I m m m' 'F m m m'
'P 4/m' 'I 4/m'
'P 4/m m m' 'I 4/m m m'
'P -3' 'R -3'
'P -3 m 1' 'R -3 m'
'P -3 1 m'
'P 6/m'
'P 6/m m m'
'P m -3' 'I m -3' 'F m -3'
'P m -3 m' 'I m -3 m' 'F m -3 m'
_item_description.description
; The Hermann-Mauguin symbol of the type of that centrosymmetric
symmorphic space group to which the Patterson function belongs,
see International Tables for Crystallography Vol A Table 2.5.1.
A space or underline separates each symbol referring to
different axes. Subscripts should appear without special
symbols. Bars should be given as negative signs before
the number to which they apply.
;
_item_type.code char
save_
#------------------------------------------
save__space_group.point_group_H-M
_item.name '_space_group.point_group_H-M'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case -4 4/m
_item_description.description
; The Hermann-Mauguin symbol denoting the geometric crystal
class of space groups to which the space group belongs, and
the geometric crystal class of point groups to which the
point group of the space group belongs.
;
_item_type.code char
save_
#-----------------------------------------
save__space_group.reference_setting
_item.name '_space_group.reference_setting'
_item.category_id space_group
_item.mandatory_code no
_item_description.description
; The reference setting of a given space group is the setting
chosen by the International Union of Crystallography as a
unique setting to which other settings can be referred
using the transformation matrix column pair given in
*.transform_rotation_xyz and *.transform_origin_shift.
The settings are given in the enumeration list in the form
'_space_group.it_number':'_space_group.name_Hall'. The
space group number defines the space group type and the
Hall symbol specifies the symmetry generators referred to
the reference coordinate system.
The reference settings chosen are identical to those listed in
International Tables for Crystallography Vol. A. For the cases
where more than one setting is given, the following choices
have been made.
For monoclinic space groups: unique axis b and cell choice 1.
For space groups with two origins: origin choice 2 (origin at
inversion center indicated by adding :2 to the Hermann-Mauguin
symbol in the enumeration list).
For rhombohedral space groups: hexagonal axes (indicated by
adding :h to the Hermann-Mauguin symbol in the enumeration list.
(Based on http://xtal.crystal.uwa.edu.au/, (select 'Docs',
select 'space-Group Symbols') Symmetry table of Ralf W.
Grosse-Kunstleve, ETH, Zurich.)
The enumeration list may be extracted from the dictionary
and stored as a separate CIF that can be referred to as
required.
;
_item_type.code char
loop_
_item_enumeration.value
_item_enumeration.detail
001:P_1 'C1^1 P_1'
002:-P_1 'Ci^1 P_-1'
003:P_2y 'C2^1 P_1_2_1'
004:P_2yb 'C2^2 P_1_21_1'
005:C_2y 'C2^3 C_1_2_1'
006:P_-2y 'Cs^1 P_1_m_1'
007:P_-2yc 'Cs^2 P_1_c_1'
008:C_-2y 'Cs^3 C_1_m_1'
009:C_-2yc 'Cs^4 C_1_c_1'
010:-P_2y 'C2h^1 P_1_2/m_1'
011:-P_2yb 'C2h^2 P_1_21/m_1'
012:-C_2y 'C2h^3 C_1_2/m_1'
013:-P_2yc 'C2h^4 P_1_2/c_1'
014:-P_2ybc 'C2h^5 P_1_21/c_1'
015:-C_2yc 'C2h^6 C_1_2/c_1'
016:P_2_2 'D2^1 P_2_2_2'
017:P_2c_2 'D2^2 P_2_2_21'
018:P_2_2ab 'D2^3 P_21_21_2'
019:P_2ac_2ab 'D2^4 P_21_21_21'
020:C_2c_2 'D2^5 C_2_2_21'
021:C_2_2 'D2^6 C_2_2_2'
022:F_2_2 'D2^7 F_2_2_2'
023:I_2_2 'D2^8 I_2_2_2'
024:I_2b_2c 'D2^9 I_21_21_21'
025:P_2_-2 'C2v^1 P_m_m_2'
026:P_2c_-2 'C2v^2 P_m_c_21'
027:P_2_-2c 'C2v^3 P_c_c_2'
028:P_2_-2a 'C2v^4 P_m_a_2'
029:P_2c_-2ac 'C2v^5 P_c_a_21'
030:P_2_-2bc 'C2v^6 P_n_c_2'
031:P_2ac_-2 'C2v^7 P_m_n_21'
032:P_2_-2ab 'C2v^8 P_b_a_2'
033:P_2c_-2n 'C2v^9 P_n_a_21'
034:P_2_-2n 'C2v^10 P_n_n_2'
035:C_2_-2 'C2v^11 C_m_m_2'
036:C_2c_-2 'C2v^12 C_m_c_21'
037:C_2_-2c 'C2v^13 C_c_c_2'
038:A_2_-2 'C2v^14 A_m_m_2'
039:A_2_-2b 'C2v^15 A_b_m_2'
040:A_2_-2a 'C2v^16 A_m_a_2'
041:A_2_-2ab 'C2v^17 A_b_a_2'
042:F_2_-2 'C2v^18 F_m_m_2'
043:F_2_-2d 'C2v^19 F_d_d_2'
044:I_2_-2 'C2v^20 I_m_m_2'
045:I_2_-2c 'C2v^21 I_b_a_2'
046:I_2_-2a 'C2v^22 I_m_a_2'
047:-P_2_2 'D2h^1 P_m_m_m'
048:-P_2ab_2bc 'D2h^2 P_n_n_n:2'
049:-P_2_2c 'D2h^3 P_c_c_m'
050:-P_2ab_2b 'D2h^4 P_b_a_n:2'
051:-P_2a_2a 'D2h^5 P_m_m_a'
052:-P_2a_2bc 'D2h^6 P_n_n_a'
053:-P_2ac_2 'D2h^7 P_m_n_a'
054:-P_2a_2ac 'D2h^8 P_c_c_a'
055:-P_2_2ab 'D2h^9 P_b_a_m'
056:-P_2ab_2ac 'D2h^10 P_c_c_n'
057:-P_2c_2b 'D2h^11 P_b_c_m'
058:-P_2_2n 'D2h^12 P_n_n_m'
059:-P_2ab_2a 'D2h^13 P_m_m_n:2'
060:-P_2n_2ab 'D2h^14 P_b_c_n'
061:-P_2ac_2ab 'D2h^15 P_b_c_a'
062:-P_2ac_2n 'D2h^16 P_n_m_a'
063:-C_2c_2 'D2h^17 C_m_c_m'
064:-C_2ac_2 'D2h^18 C_m_c_a'
065:-C_2_2 'D2h^19 C_m_m_m'
066:-C_2_2c 'D2h^20 C_c_c_m'
067:-C_2a_2 'D2h^21 C_m_m_a'
068:-C_2a_2ac 'D2h^22 C_c_c_a:2'
069:-F_2_2 'D2h^23 F_m_m_m'
070:-F_2uv_2vw 'D2h^24 F_d_d_d:2'
071:-I_2_2 'D2h^25 I_m_m_m'
072:-I_2_2c 'D2h^26 I_b_a_m'
073:-I_2b_2c 'D2h^27 I_b_c_a'
074:-I_2b_2 'D2h^28 I_m_m_a'
075:P_4 'C4^1 P_4'
076:P_4w 'C4^2 P_41'
077:P_4c 'C4^3 P_42'
078:P_4cw 'C4^4 P_43'
079:I_4 'C4^5 I_4'
080:I_4bw 'C4^6 I_41'
081:P_-4 'S4^1 P_-4'
082:I_-4 'S4^2 I_-4'
083:-P_4 'C4h^1 P_4/m'
084:-P_4c 'C4h^2 P_42/m'
085:-P_4a 'C4h^3 P_4/n:2'
086:-P_4bc 'C4h^4 P_42/n:2'
087:-I_4 'C4h^5 I_4/m'
088:-I_4ad 'C4h^6 I_41/a:2'
089:P_4_2 'D4^1 P_4_2_2'
090:P_4ab_2ab 'D4^2 P_4_21_2'
091:P_4w_2c 'D4^3 P_41_2_2'
092:P_4abw_2nw 'D4^4 P_41_21_2'
093:P_4c_2 'D4^5 P_42_2_2'
094:P_4n_2n 'D4^6 P_42_21_2'
095:P_4cw_2c 'D4^7 P_43_2_2'
096:P_4nw_2abw 'D4^8 P_43_21_2'
097:I_4_2 'D4^9 I_4_2_2'
098:I_4bw_2bw 'D4^10 I_41_2_2'
099:P_4_-2 'C4v^1 P_4_m_m'
100:P_4_-2ab 'C4v^2 P_4_b_m'
101:P_4c_-2c 'C4v^3 P_42_c_m'
102:P_4n_-2n 'C4v^4 P_42_n_m'
103:P_4_-2c 'C4v^5 P_4_c_c'
104:P_4_-2n 'C4v^6 P_4_n_c'
105:P_4c_-2 'C4v^7 P_42_m_c'
106:P_4c_-2ab 'C4v^8 P_42_b_c'
107:I_4_-2 'C4v^9 I_4_m_m'
108:I_4_-2c 'C4v^10 I_4_c_m'
109:I_4bw_-2 'C4v^11 I_41_m_d'
110:I_4bw_-2c 'C4v^12 I_41_c_d'
111:P_-4_2 'D2d^1 P_-4_2_m'
112:P_-4_2c 'D2d^2 P_-4_2_c'
113:P_-4_2ab 'D2d^3 P_-4_21_m'
114:P_-4_2n 'D2d^4 P_-4_21_c'
115:P_-4_-2 'D2d^5 P_-4_m_2'
116:P_-4_-2c 'D2d^6 P_-4_c_2'
117:P_-4_-2ab 'D2d^7 P_-4_b_2'
118:P_-4_-2n 'D2d^8 P_-4_n_2'
119:I_-4_-2 'D2d^9 I_-4_m_2'
120:I_-4_-2c 'D2d^10 I_-4_c_2'
121:I_-4_2 'D2d^11 I_-4_2_m'
122:I_-4_2bw 'D2d^12 I_-4_2_d'
123:-P_4_2 'D4h^1 P_4/m_m_m'
124:-P_4_2c 'D4h^2 P_4/m_c_c'
125:-P_4a_2b 'D4h^3 P_4/n_b_m:2'
126:-P_4a_2bc 'D4h^4 P_4/n_n_c:2'
127:-P_4_2ab 'D4h^5 P_4/m_b_m'
128:-P_4_2n 'D4h^6 P_4/m_n_c'
129:-P_4a_2a 'D4h^7 P_4/n_m_m:2'
130:-P_4a_2ac 'D4h^8 P_4/n_c_c:2'
131:-P_4c_2 'D4h^9 P_42/m_m_c'
132:-P_4c_2c 'D4h^10 P_42/m_c_m'
133:-P_4ac_2b 'D4h^11 P_42/n_b_c:2'
134:-P_4ac_2bc 'D4h^12 P_42/n_n_m:2'
135:-P_4c_2ab 'D4h^13 P_42/m_b_c'
136:-P_4n_2n 'D4h^14 P_42/m_n_m'
137:-P_4ac_2a 'D4h^15 P_42/n_m_c:2'
138:-P_4ac_2ac 'D4h^16 P_42/n_c_m:2'
139:-I_4_2 'D4h^17 I_4/m_m_m'
140:-I_4_2c 'D4h^18 I_4/m_c_m'
141:-I_4bd_2 'D4h^19 I_41/a_m_d:2'
142:-I_4bd_2c 'D4h^20 I_41/a_c_d:2'
143:P_3 'C3^1 P_3'
144:P_31 'C3^2 P_31'
145:P_32 'C3^3 P_32'
146:R_3 'C3^4 R_3:h'
147:-P_3 'C3i^1 P_-3'
148:-R_3 'C3i^2 R_-3:h'
149:P_3_2 'D3^1 P_3_1_2'
150:P_3_2" 'D3^2 P_3_2_1'
151:P_31_2_(0_0_4) 'D3^3 P_31_1_2'
152:P_31_2" 'D3^4 P_31_2_1'
153:P_32_2_(0_0_2) 'D3^5 P_32_1_2'
154:P_32_2" 'D3^6 P_32_2_1'
155:R_3_2" 'D3^7 R_3_2:h'
156:P_3_-2" 'C3v^1 P_3_m_1'
157:P_3_-2 'C3v^2 P_3_1_m'
158:P_3_-2"c 'C3v^3 P_3_c_1'
159:P_3_-2c 'C3v^4 P_3_1_c'
160:R_3_-2" 'C3v^5 R_3_m:h'
161:R_3_-2"c 'C3v^6 R_3_c:h'
162:-P_3_2 'D3d^1 P_-3_1_m'
163:-P_3_2c 'D3d^2 P_-3_1_c'
164:-P_3_2" 'D3d^3 P_-3_m_1'
165:-P_3_2"c 'D3d^4 P_-3_c_1'
166:-R_3_2" 'D3d^5 R_-3_m:h'
167:-R_3_2"c 'D3d^6 R_-3_c:h'
168:P_6 'C6^1 P_6'
169:P_61 'C6^2 P_61'
170:P_65 'C6^3 P_65'
171:P_62 'C6^4 P_62'
172:P_64 'C6^5 P_64'
173:P_6c 'C6^6 P_63'
174:P_-6 'C3h^1 P_-6'
175:-P_6 'C6h^1 P_6/m'
176:-P_6c 'C6h^2 P_63/m'
177:P_6_2 'D6^1 P_6_2_2'
178:P_61_2_(0_0_5) 'D6^2 P_61_2_2'
179:P_65_2_(0_0_1) 'D6^3 P_65_2_2'
180:P_62_2_(0_0_4) 'D6^4 P_62_2_2'
181:P_64_2_(0_0_2) 'D6^5 P_64_2_2'
182:P_6c_2c 'D6^6 P_63_2_2'
183:P_6_-2 'C6v^1 P_6_m_m'
184:P_6_-2c 'C6v^2 P_6_c_c'
185:P_6c_-2 'C6v^3 P_63_c_m'
186:P_6c_-2c 'C6v^4 P_63_m_c'
187:P_-6_2 'D3h^1 P_-6_m_2'
188:P_-6c_2 'D3h^2 P_-6_c_2'
189:P_-6_-2 'D3h^3 P_-6_2_m'
190:P_-6c_-2c 'D3h^4 P_-6_2_c'
191:-P_6_2 'D6h^1 P_6/m_m_m'
192:-P_6_2c 'D6h^2 P_6/m_c_c'
193:-P_6c_2 'D6h^3 P_63/m_c_m'
194:-P_6c_2c 'D6h^4 P_63/m_m_c'
195:P_2_2_3 'T^1 P_2_3'
196:F_2_2_3 'T^2 F_2_3'
197:I_2_2_3 'T^3 I_2_3'
198:P_2ac_2ab_3 'T^4 P_21_3'
199:I_2b_2c_3 'T^5 I_21_3'
200:-P_2_2_3 'Th^1 P_m_-3'
201:-P_2ab_2bc_3 'Th^2 P_n_-3:2'
202:-F_2_2_3 'Th^3 F_m_-3'
203:-F_2uv_2vw_3 'Th^4 F_d_-3:2'
204:-I_2_2_3 'Th^5 I_m_-3'
205:-P_2ac_2ab_3 'Th^6 P_a_-3'
206:-I_2b_2c_3 'Th^7 I_a_-3'
207:P_4_2_3 'O^1 P_4_3_2'
208:P_4n_2_3 'O^2 P_42_3_2'
209:F_4_2_3 'O^3 F_4_3_2'
210:F_4d_2_3 'O^4 F_41_3_2'
211:I_4_2_3 'O^5 I_4_3_2'
212:P_4acd_2ab_3 'O^6 P_43_3_2'
213:P_4bd_2ab_3 'O^7 P_41_3_2'
214:I_4bd_2c_3 'O^8 I_41_3_2'
215:P_-4_2_3 'Td^1 P_-4_3_m'
216:F_-4_2_3 'Td^2 F_-4_3_m'
217:I_-4_2_3 'Td^3 I_-4_3_m'
218:P_-4n_2_3 'Td^4 P_-4_3_n'
219:F_-4a_2_3 'Td^5 F_-4_3_c'
220:I_-4bd_2c_3 'Td^6 I_-4_3_d'
221:-P_4_2_3 'Oh^1 P_m_-3_m'
222:-P_4a_2bc_3 'Oh^2 P_n_-3_n:2'
223:-P_4n_2_3 'Oh^3 P_m_-3_n'
224:-P_4bc_2bc_3 'Oh^4 P_n_-3_m:2'
225:-F_4_2_3 'Oh^5 F_m_-3_m'
226:-F_4a_2_3 'Oh^6 F_m_-3_c'
227:-F_4vw_2vw_3 'Oh^7 F_d_-3_m:2'
228:-F_4ud_2vw_3 'Oh^8 F_d_-3_c:2'
229:-I_4_2_3 'Oh^9 I_m_-3_m'
230:-I_4bd_2c_3 'Oh^10 I_a_-3_d'
save_
save__space_group.transform_rotation_xyz
_item.name '_space_group.transform_rotation_xyz'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail
'a,b-a,c' 'orthohexagonal to the reference hexagonal setting'
_item_description.description
; This item contains the (3x3) transformation P defined as follows:
The relation between an arbitrary setting of a space group
(basis vectors (a,b,c) origin O) and the reference coordinate
system (basis vectors (a',b',c') origin O') is determined by
an augmented affine (4x4) transformation matrix (cf. Section 5
of International Tables for Crystallography, vol. A). It
consists of (3x3) rotation matrix P=(Pij) which describes
the transformation of the row (a,b,c)
to the row of reference basis vectors (a',b',c'):
(a',b',c') = (a,b,c)P
and the (3x1) column p=(pi1) which determines the origin
shift of O with respect to reference origin O':
O' = O + p
The rotation matrix P is given as:
P11a+P21b+P31c, P12a+P22b+P32c, P13a+P23b+P33c.
Note that the bases (a',b',c') and (a,b,c) are both written
as rows. Thus, in each of the sums P11a+P21b+P31c,
P12a+P22b+P32c, P13a+P23b+P33c, a column of P is listed.
This way of presenting the matrix is different from the
xyz presentation of the symmetry operations
(cf. _space_group_symop.operation_xyz) where the matrices
of the symmetry operations are listed by rows.
The reference settings are enumerated under *.reference_setting.
;
_item_type.code char
save_
save__space_group.transform_origin_shift
_item.name '_space_group.transform_origin_shift'
_item.category_id space_group
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail 'a/2,b/2,0' 'origin shift p = (0.5,0.5,0)'
_item_description.description
; The origin shift vector, p, is defined as follows:
The relation between an arbitrary setting of a space group
(basis vectors (a,b,c) origin O) and the reference coordinate
system (basis vectors (a',b',c') origin O') is determined by
an augmented affine (4x4) transformation matrix (cf. Section 5
of International Tables for Crystallography, vol. A). It
consists of (3x3) rotation matrix P=(Pij) which describes
the transformation of the row (a,b,c) to the row of
reference basis vectors (a',b',c'):
(a',b',c') = (a,b,c)P
and the (3x1) column p=(pi1) which determines the origin
shift of O with respect to reference origin O':
O' = O + p
The reference settings are enumerated under *.reference_setting
;
_item_type.code char
save_
#####################################################
#
# CATEGORY: SPACE_GROUP_SYMOP
#
#####################################################
save_SPACE_GROUP_SYMOP
_category.id space_group_symop
_category.description
; Contains information about the symmetry operations of the
space group.
;
_category.mandatory_code no
loop_
_category_examples.detail
_category_examples.case
;
The symmetry operations for the space group P21/c
;
; loop_
_space_group_symop.id
_space_group_symop.operation_xyz
_space_group_symop.operation_description
1 x,y,z 'identity mapping'
2 -x,-y,-z 'inversion'
3 -x,1/2+y,1/2-z '2-fold screw rotation with axis in (0,y,1/4)'
4 x,1/2-y,1/2+z 'c glide reflection through the plane (x,1/4,y)'
;
_category_key.name '_space_group_symop.id'
save_
#####################################################
save__space_group_symop.generator_xyz
_item.name '_space_group_symop.generator_xyz'
_item.category_id space_group_symop
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail
'x,1/2-y,1/2+z'
; c glide reflection through the plane (x,1/4,z) chosen as
one of the generators of the space group
;
_item_description.description
; A parsable string giving one of the symmetry generators of the
space group in algebraic form. If W is a matrix representation
of the rotational part of the generator defined by the positions
and signs of x, y and z, and w is a column of translations
defined by the 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, Section 5)
When a list of symmetry generators is given, it is assumed
that the complete list of symmetry operations of the space
group (including the identity operator) can be generated
through repeated multiplication of the generators, that is,
(W3, w3) is an operation of the space group if (W2,w2) and
(W1,w1) (where (W1,w1) is applied first) are either operators
or generators and:
W3 = W2 x W1
w3 = W2 x w1 + w2
;
_item_type.code char
_item_default.value 'x,y,z'
loop_
_item_related.related_name
_item_related.function_code '_space_group_symop.operation_xyz' alternate
save_
#-----------------------------------------
save__space_group_symop.id
_item_description.description
; An arbitrary identifier that uniquely labels each symmetry
operation in the list.
;
_item_type.code char
loop_
_item.name
_item.category_id
_item.mandatory_code
'_space_group_symop.id' space_group_symop yes
loop_
_item_aliases.alias_name
_item_aliases.dictionary
_item_aliases.version
'_symmetry_equiv_pos_site_id' cif_core.dic 1.0
'_symmetry_equiv.id' cif_mm.dic 1.0
save_
#-----------------------------------------------
save__space_group_symop.operation_description
_item.name '_space_group_symop.operation_description'
_item.category_id space_group_symop
_item.mandatory_code no
_item_description.description
; An optional text description of a particular symmetry operation
of the space group.
;
_item_type.code char
loop_
_item_dependent.dependent_name
'_space_group_symop.generator_xyz'
'_space_group_symop.operation_xyz'
save_
#------------------------------------------------
save__space_group_symop.operation_xyz
_item.name '_space_group_symop.operation_xyz'
_item.category_id space_group_symop
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail
'x,1/2-y,1/2+z' 'c glide reflection through the plane (x,1/4,z)'
_item_description.description
; 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 the 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, Section 5)
When a list of symmetry operations is given, it is assumed
that the list contains all the operations of the space
group (including the identity operation) as given by the
representatives of the general position in International
Tables for Crystallography Vol. A.
;
_item_type.code char
_item_aliases.alias_name '_symmetry_equiv_pos_as_xyz'
_item_aliases.dictionary cif_core.dic
_item_aliases.version 1.0
_item_default.value 'x,y,z'
loop_
_item_related.related_name
_item_related.function_code '_space_group_symop.generator_xyz' alternate
save_
#------------------------------------------------
save__space_group_symop.sg_id
_item.name '_space_group_symop.sg_id'
_item.category_id space_group_symop
_item.mandatory_code no
loop_
_item_example.case
_item_example.detail
? ?
_item_description.description
; A child of _space_group.id allowing the symmetry operator
to be identified with a particular space group.
;
_item_type.code numb
_item_linked.child_name '_space_group_symop.sg_id'
_item_linked.parent_name '_space_group.id'
save_
#####################################################
#
# CATEGORY: SPACE_GROUP_WYCKOFF
#
# Information about the Wyckoff positions
#
#
#####################################################
save_SPACE_GROUP_WYCKOFF
_category.id space_group_Wyckoff
_category.description
; Contains information about Wyckoff positions of a space group.
Only one site can be given for each special position but the
remainder can be generated by applying the symmetry operations
stored in _space_group_symop.operation_xyz.
;
_category.mandatory_code no
loop_
_category_examples.detail
_category_examples.case
;
This example is taken from the space group F_d_-3_c (number 228
origin choice 2). For brevity only a selection of special positions
are listed. The coordinates of only one site per special position can
be given in this item, but coordinates of the other sites can be
generated using the symmetry operations given in the SPACE_GROUP_SYMOP
category.
;
;
loop_
_space_group_Wyckoff.id
_space_group_Wyckoff.multiplicity
_space_group_Wyckoff.letter
_space_group_Wyckoff.site_symmetry
_space_group_Wyckoff.coord_xyz
1 192 h 1 x,y,z
2 96 g ..2 1/4,y,-y
3 96 f 2.. x,1/8,1/8
4 32 b .32 1/4,1/4,1/4
;
_category_key.name '_space_group_Wyckoff.id'
save_
save__space_group_Wyckoff.coords_xyz
_item.name '_space_group_Wyckoff.coords_xyz'
_item.category_id space_group_Wyckoff
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail
'x,1/2,0' 'Coordinates of a Wyckoff site with 2.. symmetry'
_item_description.description
; Coordinates of one site of a Wyckoff position expressed in
terms of its fractional coordinates (x,y,z) in the unit cell.
To generate the coordinates of all sites of this Wyckoff
position it is necessary to multiply these coordinates by the
symmetry operations stored in space_group_symop.operation_xyz.
;
_item_type.code char
_item_default.value 'x,y,z'
save_
#----------------------------------------
save__space_group_Wyckoff.id
loop_
_item.name
_item.category_id
_item.mandatory_code
'_space_group_Wyckoff.id' space_group_Wyckoff yes
_item_description.description
; An arbitrary identifier that is unique to a particular Wyckoff
position.
;
_item_type.code char
save_
#---------------------------------------------
save__space_group_Wyckoff.letter
_item.name '_space_group_Wyckoff.letter'
_item.category_id space_group_Wyckoff
_item.mandatory_code no
_item_description.description
; The Wyckoff letter as given in International Tables for
Crystallography Vol. A associated with this position.
;
_item_type.code char
loop_
_item_enumeration.value
a b c d e f g h i j k l m n o p q r s t u v w x y z \a
save_
#-----------------------------------------------
save__space_group_Wyckoff.multiplicity
_item.name '_space_group_Wyckoff.multiplicity'
_item.category_id space_group_Wyckoff
_item.mandatory_code no
_item_description.description
; The multiplicity of this Wyckoff position as given in
International Tables Vol A. It is the number of equivalent
sites per conventional unit cell.
;
_item_type.code numb
loop_
_item_range.maximum
_item_range.minimum . 1
1 1
save_
#------------------------------------------------
save__space_group_Wyckoff.sg_id
_item.name '_space_group_Wyckoff.sg_id'
_item.category_id space_group_Wyckoff
_item.mandatory_code no
loop_
_item_example.case
_item_example.detail
? ?
_item_description.description
; A child of _space_group.id allowing the Wyckoff position
to be identified with a particular space group.
;
_item_type.code char
_item_linked.child_name '_space_group_Wyckoff.sg_id'
_item_linked.parent_name '_space_group.id'
save_
#------------------------------------------------
save__space_group_Wyckoff.site_symmetry
_item.name '_space_group_Wyckoff.site_symmetry'
_item.category_id space_group_Wyckoff
_item.mandatory_code no
loop_
_item_examples.case
_item_examples.detail
2.22 'Position 2b in space group number 94, P_42_21_2'
42.2 'Position 6b in space group number 222, P_n_-3_n'
2..
; Site symmetry for the Wyckoff position 96f in space group 228,
F_d_-3_c. The site symmetry group is isomorphic to the point
group 2 with the 2-fold axis along one of the {100} directions.
;
_item_description.description
; The subgroup of the space group that leaves the point fixed.
It is isomorphic to a subgroup of the point group of the
space group. The site symmetry symbol indicates the symmetry
in the symmetry direction determined by the Hermann-Mauguin
symbol of the space group (see International Tables for
Crystallography Vol A Section 2.12).
;
_item_type.code char
save_
###################################################
##
loop_
_dictionary_history.version
_dictionary_history.update
_dictionary_history.revision
0.01 1998-11-27
; (I.D.Brown)
Creation of first draft of the dictionary.
Contains the categories SPACE_GROUP, SPACE_GROUP_POS,
SPACE_GROUP_REFLNS and SPACE_GROUP_COORD
;
0.02 1999-02-15
; (IDB)
Changes made in response to suggestions from the project group. New
categories introduced
SPACE_GROUP_SYMOP
SPACE_GROUP_ASYM.
The following category name changes were made:
SPACE_GROUP_POS to SPACE_GROUP_WYCKOFF
SPACE_GROUP_REFLNS to SPACE_GROUP_WYCKOFF_CONDITIONS
SPACE_GROUP_COORD to SPACE_GROUP_WYCKOFF_COORD
The items are arranged in alphabetical order
Many other changes made in response to comments received
including new data names for space group names
;
0.03 1999-09-01
; IDB
Definitions of _space_group.IT_number, *.name_schoenflies
*.Bravais_type, *point_group_H-M, *.crystal_system and *.Laue_class
changed to those supplied by Litvin and Kopsky.
*.setting_code changed to *.it_coordinate_system_code.
*.name_H-M-K dropped.
*.Patterson_symmetry_H-M changed to *.Patterson_name_H-M and
enumeration list corrected.
*.reference_setting added
In category space_group_symop 'operator' changed to 'operation'.
_space_group_symop.operation_matrix changed to conform to IT.
_space_group_symop.generator_* added.
_space_group.reference_setting added.
_space_group_Wyckoff.* and related categories rewritten to avoid
conflicting parent-child relations. Removal of *_coord.* and addition
of *_cond_link.*
;
0.04 1999-11-01
; IDB
List of reference settings imported from Ralf Grosse-Kunstleve
supplied 1999-10-29 by RWGK based on http://xtal.crystal.uwa.edu.au/
(Select 'Docs', Select 'space Group Symbols') Symmetry table of Ralf
W. Grosse-Kunstleve, ETH, Zuerich.
version June 1995
updated September 29 1995
updated July 9 1997
last updated July 24 1998
Matrices expanded into separate items for each element.
References added for *_wyckoff.site_symmetry and
*.IT_coordinate_system_code.
*_asym category deleted.
Numerous typographical errors corrected
;
0.05 2000-01-12
; IDB
Further clarifications to definitions as suggested by Aroyo,
Wondratschek, Madariaga, Litvin and Grosse-Kunstleve.
Removal of all matrix forms of matrices (leaving xyz form) in the hope
that a new DDL will make matrix representation simpler.
Removal of *_Wyckoff_cond and *_Wyckoff_cond_link categories until a
new DDL simplifies their structure.
Added _space_group.transform_* items
;
0.06 2000-05-04
; IDB
Further clarification of definitions as suggested by Aroyo,
Wondratschek, Madariaga and Grosse-Kunstleve, particularly
clarification of the Hermann-Mauguin symbols and Bravais types and
changes to conform to the usage of ITA.
;
0.07 2000-07-18
; IDB
Further clarifications and corrections from Wondratschek and
Grosse-Kunstleve. Dictionary checked in vcif.
Brian McMahon:
Structural review for COMCIFS. Some reformatting and cleaning up of
minor typos. Checked against vcif and cyclops.
;
0.08 2000-07-20
; J. Westbrook
Miscellaneous corrections and reformatting from software scan.
;
0.09 2001-05-31
; IDB
The links between the space_group category and the
space_group_symop and space_group_Wyckoff categories are
corrected as well as the links between space_group_symop and the
various geom_ categories.
Brian McMahon:
Changed type of _space_group_symop.sg_id to numb at request of IDB.
;
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