Three Dimensions
Point groups in three dimensions, sometimes called molecular point groups, after their wide use in studying the symmetries of small molecules.
They come in 7 infinite families of axial or prismatic groups, and 7 additional polyhedral or Platonic groups. In Schönflies notation,*
- Axial groups: Cn, S2n, Cnh, Cnv, Dn, Dnd, Dnh
- Polyhedral groups: T, Td, Th, O, Oh, I, Ih
Applying the crystallographic restriction theorem to these groups yields 32 Crystallographic point groups.
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Read more about this topic: Point Group
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