Ogdohedry
- Page ID
- 19070
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The point group of a crystal is called ogdohedry if it is a subgroup of index 8 of the point group of its lattice.
In the three dimensional space there is only one ogdohedry: it corresponds to the geometric crystal class 3 of crystals belonging to the hexagonal lattice system (in case rhombohedral crystals, it corresponds instead to a tetartohedry).