Crystallographic Information Framework

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Restraints dictionary version 1.0

_restr_U_rigid_site_symmetry_

Names:
'_restr_U_rigid_site_symmetry_1' '_restr_U_rigid_site_symmetry_2'

Definition:

   The site symmetries of the two atoms that define the rigid bond.

   The symmetry code of each atom site is given as the 
	       symmetry-equivalent position number 'n' and the 
	       cell translation number 'klm'. These numbers are 
	       combined to form the code 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 (formerly _symmetry_equiv_pos_site_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 rigid 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:

. no symmetry or translation to site
4 4th symmetry operation applied
7_645 7th symm. posn.; +a on x; -b on y

Appears in list containing restr_U_rigid_atom_site_label_
Enumeration default: 1_555

Type: char

Category: restr_U_rigid