Carbon 2pzMultiplehyphen;Center Dipolar Interaction Integrals in the Matrix Element over LCAO Molecular Orbitals

摘要

A method has been devised to enumerate, according to magnitude, all significant multiplehyphen;center integrals that occur in the LCAO expansion of a matrix element belonging to the dipolar interaction operator over products of molecular orbitals. The coefficient, which consists of a product of atomic vector (expansion) coefficients, pertaining to each multiplehyphen;center integral was evaluated by an IBM 7090 FORTRAN program derived from the same logical principles as the above enumeration. The multiplehyphen;center dipolar interaction integrals were computed by (1) the Mullikenmdash;Hameka approximation and (2) the Gaussian wavefunction method. Results from both methods for the integrals of naphthalene are compared. Results for twohyphen;center integrals using the Gaussian wavefunction method for a series of interatomic distances up toR=18.413 Bohr radii are also given.