The following table lists the notations for the thirty-two crystallographic point group, organized by crystal system [1,2]. The Hermann-Mauguin System is often referred to as the International System. This convention is commonly applied to the decription of crystallographic point and space groups in solid-state chemistry and materials science. The Schoenflies notation system has often been (and still is) used to describe the symmetry of molecules [3].
Crystal system Hermann-Mauguin notation Schoenflies notation
Triclinic 1 C1
1 Ci
Monoclinic 2 C2
m Cs
2/m C2h
Orthorhombic 222 D2
mm2 C2v
mmm D2h
Tetragonal 4 C4
4 S4
4/m C4h
422 D4
4mm C4v
42m D2d
4/m mm D4h
Trigonal 3 C3
3 C3i
32 D3
3m C3v
3m D3d
Hexagonal 6 C6
6 C3h
6/m C6h
622 D6
6mm C6v
6m2 D3h
6/m mm D6h
Cubic 23 T
m3 Th
432 O
43m Td
m3m Oh
The numbers and letters in a Hermann-Mauguin notation encode point symmetry elements [2]:

- the rotation axes 1, 2, 3, 4, and 6;
- the inversion axes 1, 2, 3, 4, and 6;
- the mirror plane m (equivalent to 2).

References and Notes

[1] Gregory S. Rohrer: Structure and Bonding in Crystalline Materials, Cambridge University Press, Cambridge, UK, 2001. See Chapter 3 Symmetry in Crystal Structures and Table 3.1 therein.
[2] Anthony R. West: Solid State Chemistry and Its Applications, John Wiley & Sons, Chichester, 1984. See Chapter 6 Point Groups, Space Groups and Crystal Structure and Table 6.2 therein.
[3] David M. Bishop: Group Theory and Chemistry, Dover Publications, Inc., New York, 1973.
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