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
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