Definition:
The SPACE_GROUP_SYMOP category introduced in the symmetry CIF dictionary (cif_sym.dic) is intended to replace the original core SYMMETRY_EQUIV category. It contains information about the symmetry operations of the space group. For modulated structures, superspace-group descriptions may be included in the same category, but include the _ssg_ flag to indicate their dimensionality of > 3.Example:
Example 1 - example corresponding to the one-dimensional incommensurately
modulated structure of K~2~SeO~4~.
loop_
_space_group_symop_ssg_id
_space_group_symop_ssg_operation_algebraic
1 x1,x2,x3,x4
2 1/2+x1,1/2-x2,1/2-x3,x4
3 1/2-x1,1/2+x2,-x3,1/2-x4
4 -x1,-x2,1/2+x3,1/2-x4
5 -x1,-x2,-x3,-x4
6 1/2-x1,1/2+x2,1/2+x3,-x4
7 1/2+x1,1/2-x2,x3,1/2+x4
8 x1,x2,1/2-x3,1/2+x4
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Type: null
Category: category_overview
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