Geometric crystal class
- Page ID
- 18942
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Geometric crystal classes (or simply 'crystal classes') classify the symmetry groups of the external shape of macroscopic crystals, namely according to the morphological symmetry. There are 10 two-dimensional geometric crystal classes and 32 three-dimensional geometric crystal classes, in one to one correspondence with the 10 and 32 types of point groups in E2 and E3, respectively.
See also
- Section 8.2.4 of International Tables for Crystallography, Volume A