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Modulated and composite structures dictionary (msCIF) version 1.0.1

_geom_torsion_site_ssg_symmetry_

Names:
'_geom_torsion_site_ssg_symmetry_1' '_geom_torsion_site_ssg_symmetry_2' '_geom_torsion_site_ssg_symmetry_3' '_geom_torsion_site_ssg_symmetry_4'

Definition:

   The symmetry code of each atom site as the symmetry operation
   number 'n' and the higher-dimensional translation 'm1...mp'.
   These numbers are combined to form the code 'n m1...mp' or
   n_m1...mp. The character string n_m1...mp is composed as follows:
   'n' refers to the symmetry operation that is applied to the
   superspace coordinates. It must match a number given in
   _space_group_symop_ssg_id. 'm1...mp' refer to the translations
   that are subsequently applied to the symmetry-transformed
   coordinates to generate the atom used in calculating the angle.
   These translations (t1,...tp) are related to (m1...mp) by the
   relations m1=5+t1, ..., mp=5+tp. By adding 5 to the
   translations, the use of negative numbers is avoided. The number
   'p' must agree with (_cell_modulation_dimension + 3). If there
   are no cell translations, the translation number may be omitted.
   If no symmetry operations or translations are applicable,
   then a single full stop '.' is used.

Examples:

. no symmetry or translation to site
4 4th symmetry operation applied
7_6455 7th symmetry position; +a on x, -b on y

Appears in list containing _geom_torsion_atom_site_label_

Type: char

Category: geom_torsion