Core CIF Dictionary version 2.3

_space_group_[]

Name

Category: category_overview

Data type: null

Examples:

    _space_group_id                 1
    _space_group_name_H-M_alt       'C 2/c'
    _space_group_IT_number          15
    _space_group_name_Hall          '-C 2yc'
    _space_group_crystal_system     monoclinic

Example 1 -

Definition

    	
   Contains all the data items that refer to the space group as a
   whole, such as its name, crystal system etc. It may be looped,
   for example, in a list of space groups and their properties.

   Only a subset of the SPACE_GROUP category items appear in the 
   core dictionary.  The remainder are found in the cif_sym
   dictionary.

   Space group types are identified by their International Tables
   for Crystallography Vol. A number or Schoenflies symbol.  
   Specific settings of the space groups can be identified either
   by their Hall symbol or by specifying their symmetry operations.

   The commonly-used Hermann-Mauguin symbol determines the
   space group type uniquely but several different Hermann-Mauguin
   symbols may refer to the same space group type. It contains
   information on the choice of the basis, but not on the
   choice of origin.  Different formats for the Hermann-Mauguin
   symbol are found in the cif_sym dictionary.