Electron microscopy
 
Holohedral Point Groups
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The point group is called a holohedral group if it has the highest point-group symmetry in a specific crystal system and thus it corresponds to the symmetry of the lattice. Therefore, there are seven holohedral point groups that have the symmetry of the seven crystal systems.

Table 1461. Holohedral and merohedral crystallographic point groups.

Crystal system  Holohedral point groups Merohedral point groups
Triclinic -1 1
Monoclinic 2/m 2, m
Orthorhombic mmm mm2, 222
Tetragonal 4/mmm 422, 4mm, -42m, 4/m, -4, 4
Trigonal
-3m 32, 3m, -3, 3
Hexagonal 6/mmm 622, 6mm, -62m, 6/m, -6, 6
Cubic
m-3m 432, -43m, m-3, 23

 

 

 

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