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Low Symmetry Point Groups
Low symmetry point groups include the C1, Cs, and Ci groups
|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 Td, Oh, Ih, 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.
|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-|