List of finite spherical symmetry groups
Finite spherical symmetry groups are also called point groups in three dimensions. There are five fundamental symmetry classes which have triangular fundamental domains: dihedral, cyclic, tetrahedral, octahedral, and icosahedral symmetry.
This article lists the groups by Schoenflies notation, Coxeter notation, orbifold notation, and order. John Conway uses a variation of the Schoenflies notation, based on the groups' quaternion algebraic structure, labeled by one or two upper case letters, and whole number subscripts. The group order is defined as the subscript, unless the order is doubled for symbols with a plus or minus, "±", prefix, which implies a central inversion.
Hermann–Mauguin notation is also given. The crystallography groups, 32 in total, are a subset with element orders 2, 3, 4 and 6.
Involutional symmetry
There are four involutional groups: no symmetry, reflection symmetry, 2-fold rotational symmetry, and central point symmetry.Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
1 | 11 | C1 | C1 | ]+ | 1 | ||
2 | 22 | D1 = C2 | D2 = C2 | + | 2 | ||
× | Ci = S2 | CC2 | 2 | ||||
= m | 1 | * | Cs = C1v = C1h | ±C1 = CD2 | 2 |
Cyclic symmetry
There are four infinite cyclic symmetry families, with n = 2 or higher.Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
2× | S4 | CC4 | 4 | ||||
2/m | 2 | 2* | C2h = D1d | ±C2 = ±D2 | 4 |
Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
2 3 4 5 6 n | 22 33 44 55 66 nn | C2 C3 C4 C5 C6 Cn | C2 C3 C4 C5 C6 Cn | + + + + + + | 2 3 4 5 6 n | ||
2mm 3m 4mm 5m 6mm nm nmm | 2 3 4 5 6 n | *22
| C2vC3v C4v C5v C6v Cnv | CD4 CD6 CD8 CD10 CD12 CD2n | 4 6 8 10 12 2n | ||
- | 3× 4× 5× 6× n× | S6 S8 S10 S12 S2n | ±C3 CC8 ±C5 CC12 CC2n / ±Cn | 6 8 10 12 2n | |||
3/m= 4/m 5/m= 6/m n/m | 2 2 2 2 2 | 3* 4* 5* 6* n* | C3h C4h C5h C6h Cnh | CC6 ±C4 CC10 ±C6 ±Cn / CC2n | 6 8 10 12 2n |
Dihedral symmetry
There are three infinite dihedral symmetry families, with n = 2 or higher.Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
222 | . | 222 | D2 | D4 | + | 4 | |
2m | 4 | 2*2 | D2d | DD8 | 8 | ||
mmm | 22 | *222 | D2h | ±D4 | 8 |
Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
32 422 52 622 | . . . . . | 223 224 225 226 22n | D3 D4 D5 D6 Dn | D6 D8 D10 D12 D2n | + + + + + | 6 8 10 12 2n | |
m 2m m .2m | 6 8 10. 12. n | 2*3 2*4 2*5 2*6 2*n | D3d D4d D5d D6d Dnd | ±D6 DD16 ±D10 DD24 DD4n / ±D2n | 12 16 20 24 4n | ||
m2 4/mmm m2 6/mmm | 32 42 52 62 n2 | *223
| D3hD4h D5h D6h Dnh | DD12 ±D8 DD20 ±D12 ±D2n / DD4n | 12 16 20 24 4n |
Polyhedral symmetry
There are three types of polyhedral symmetry: tetrahedral symmetry, octahedral symmetry, and icosahedral symmetry, named after the triangle-faced regular polyhedra with these symmetries.Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
23 | . | 332 | T | T | + = + | 12 | |
m | 4 | 3*2 | Th | ±T | 24 | ||
3m | 33 | *332 | Td | TO | = | 24 |
Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
432 | . | 432 | O | O | + = | 24 | |
mm | 43 | *432 | Oh | ±O | = | 48 |
Intl | Geo | Orb. | Schön. | Con. | Cox. | Ord. | Fund. domain |
532 | . | 532 | I | I | + | 60 | |
2/m | 53 | *532 | Ih | ±I | 120 |