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Difference between revisions of "Ogdohedry"

From Online Dictionary of Crystallography

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== See also ==
 
== See also ==
 
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*Section 3.2.1 of ''International Tables of Crystallography, Volume A'', 6<sup>th</sup> edition
Section 9.1 of ''International Tables of Crystallography, Volume A''
 
  
  
 
[[Category:Fundamental crystallography]]<br>
 
[[Category:Fundamental crystallography]]<br>
 
[[Category:Morphological crystallography]]
 
[[Category:Morphological crystallography]]

Revision as of 16:21, 10 April 2017

Ogdoédrie (Fr). Ogdoedria (Sp). Ogdoedria (It). 八面像 (Ja)


Definition

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).

See also

  • Section 3.2.1 of International Tables of Crystallography, Volume A, 6th edition