Symmetry operations are operations that leave the molecule apparently unchanged. In each molecule there can be any number or none of these:

Rotations (C_{n}) These are rotations about the axes of symmetry. n denotes 360º divided by the number for the rotation. For example C_{2} = 180º C_{3} = 120º C_{4} = 90º C_{5} = 72º C_{6} = 60º Other types of Symmetry Operations Improper rotations (S_{n}) Inversion centre (i) Reflections (s_{h}, s_{d} and s_{v}) Identity operation (E)

Rotations (C_{n})

These are rotations about the axes of symmetry. n denotes 360º divided by the number for the rotation. For example

These are rotations about the axes of symmetry. n denotes 360º divided by the number for the rotation.

For example