Everything about Molecular Symmetry totally explained
Molecular symmetry in
chemistry describes the
symmetry present in
molecules and the classification of molecules according to their symmetry. Molecular symmetry is a fundamental concept in chemistry, as it can predict or explain many of a molecule's
chemical properties, such as its
dipole moment and its allowed
spectroscopic transitions (based on
selection rules such as the
Laporte rule). Virtually every university level textbook on
physical chemistry,
quantum chemistry, and
inorganic chemistry devotes a chapter to symmetry.
While various frameworks for the study of molecular symmetry exist,
group theory is the predominant one. This framework is also useful in studying the symmetry of
molecular orbitals, with applications such as the
Hückel method,
ligand field theory, and the
Woodward-Hoffmann rules. Another framework on a larger scale is the use of
crystal systems to describe
crystallographic symmetry in bulk materials.
Many techniques exist for the practical assessment of molecular symmetry, including
X-ray crystallography and various forms of
spectroscopy.
Spectroscopic notation is based on symmetry considerations.
Symmetry concepts
The study of symmetry in molecules is an adaptation of mathematical
group theory.
Elements
The symmetry of a molecule can be described by 5 types of
symmetry elements.
- Symmetry axis: an axis around which a rotation by
