Point Groups for Various Molecules

The molecules most commonly encountered generally possess a number of symmetry elements. Every molecule is associated with a point group, where the point group is defined as the collection of symmetry operations which when applied about a point leave the molecular configuration unchanged in space, while the point itself remains at rest, or more precisely, transposes into itself. There is a 

Point groups which combine several symmetry elements are described below. Common point groups and their symmetry elements are summarized in Table 4-II. 

Point Groups and C h. Molecules having a rotational axis of symmetry and mirror planes containing the rotational axis are designated as C y. The number of planes is determined by the value of since these planes are parallel to the rotational axis and are symmetrically arranged about it at angles 360 

The point group has one plane of symmetry and the identity / as its symmetry elements. It is often given the symbol Q. An example of a symmetry is the nonlinear molecule NOCl. 

Many molecules belong to the point group C2v, H2O is an example. To illustrate this symmetry for H2O, let us examine 

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