Click here to see a lecture on this topic . Low Symmetry Point Groups Low symmetry point groups include the C 1 , C s , and C i groups Group Description Example C1 only the identity operation (E) CHFClBr Cs only the identity operation (E) and one mirror plane C2H2ClBr Ci only the identity operation (E) and a center of inversion (i) C2H2Cl2Br High Symmetry Point Groups High symmetry point groups include the T d , O h , I h , C ∞v , and D ∞h groups. The table below describes their characteristic symmetry operations. The full set of symmetry operations included in the point group is described in the corresponding character table. Group Description Example C∞v linear molecule with an infinite number of rotation axes and vertical mirror planes (σv) HBr D∞h linear molecule with an infinite number of rotation axes, vertical mirror planes (σv), perpendicular C2 axes, a horizontal mirror plane (σh), and an inversion center (i) CO2 Td typically have tetrahedral geometry, with 4 C4 axes, 3 C2 axes, 3 S4 axes, and 6 dihedral mirror planes (σd) CH4 Oh typically have octahedral geometry, with 3 C4 axes, 4 C3 axes, and an inversion center (i) as characteristic symmetry operations SF6 Ih typically have an icosahedral structure, with 6 C5 axes as characteristic symmetry operations B12H122- See Also Symmetry Gallery