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| cP | cF |
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| cI |
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| cP | cF |
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| cI |
The symmetry constraints on cubic lattices are due to the body-diagonal threefold rotation axis plus axes of order 2 parallel to each of the cell edges. This constrains all of the unit-cell angles to 90° and all of the unit-cell lengths to be equal, i.e., a = b = c. Single-faced (A, B, or C) lattice centring is incompatible with the presence of threefold symmetry.
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| © Copyright 1995-2006. Birkbeck College, University of London. | Author(s): Jeremy Karl Cockcroft |