Definition:
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:
. | 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 _geom_contact_atom_site_label_
Type: char
Category: geom_contact
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