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Symmetry dictionary (symCIF) version 1.0.1




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

   Space-group types are identified by their number as listed in
   International Tables for Crystallography Volume A, or by their
   Schoenflies symbol. Specific settings of the space groups can
   be identified by their Hall symbol, by specifying their
   symmetry operations or generators, or by giving the
   transformation that relates the specific setting to the
   reference setting based on International Tables Volume A and
   stored in this dictionary.

   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. A
   Hermann-Mauguin symbol contains information on the choice of
   the basis, but not on the choice of origin.

   Ref: International Tables for Crystallography (2002). Volume A,
        Space-group symmetry, edited by Th. Hahn, 5th ed.
        Dordrecht: Kluwer Academic Publishers.


Example 1 - description of the C2/c space group, No. 15 in International Tables for Crystallography Volume A.
    _space_group.id                    1
    _space_group.name_H-M_ref            'C 2/c'
    _space_group.name_Schoenflies      C2h.6
    _space_group.IT_number             15
    _space_group.name_Hall           '-C 2yc'
    _space_group.Bravais_type          mS
    _space_group.Laue_class            2/m
    _space_group.crystal_system        monoclinic
    _space_group.centring_type         C
    _space_group.Patterson_name_H-M  'C 2/m'

Category key:

Mandatory category: yes