The bond orders of alternant hydrocarbon molecules

Abstract

Abstract The equations which determine the molecular orbitals of an alternant hydrocarbon molecule are discussed. It is proved that the bond orders can be calculated algebraically by various methods without solving the eigenvalue equations. In particular, it is possible to express the bond orders as the sum of a converging series of matrices each of whose terms has a simple interpretation. The naphthalene and benzpyrene molecules are used as illustrations of the various methods. These methods are particularly useful when applied to self-consistent field treatments of these molecules.