Core dictionary (coreCIF) version 2.4.5
The number as assigned in International Tables for Crystallography Vol. A, specifying the proper affine class (i.e. the orientation-preserving affine class) of space groups (crystallographic space-group type) to which the space group belongs. This number defines the space-group type but not the coordinate system in which it is expressed.
May appear in list containing _space_group_id
The permitted range is 1 -> 230
Related item: _symmetry_Int_Tables_number (alternate)