EXTENSION OF THE COULOMB-HOLE-HARTREE-FOCK THEORY TO MOLECULES

The Coulomb-Hole-Hartree-Fock method introduced by E. Clementi in the early 1960s and reparametrized more recently by S. Chakraworty and E. Clementi to compute the correlated electronic energy in atomic systems , is here extended to compute molecules. The new parametrization is ob tained empirically by fitting first and second atomic ionization poten tials from He to Ca and a few diatomic molecules. The present formulat ion makes use of either one or more determinants in order to ensure pr oper dissociation products, following the early proposal of G. C. Lie and E. Clementi in the context of density functional computations for molecular systems. The new formulation is tested against the dissociat ion energies of a large number of molecules and it is found satisfacto ry. (C) 1995 John Wiley and Sons, Inc.