Prolate-spheroidal orbitals for homonuclear and heteronuclear diatomic molecules. I. Basic procedure

In view of further determination of shielded homonuclear and heteronuclear diatomic orbitals, the problem of one electron in the field of two fixed nuclei and a cylindrically symmetric parametric potential is investigated. The simultaneous resolution of the separated equations, in prolate-spheroidal coordinates, is performed by a matricial technique using a Newton-Raphson scheme; as the orbitals are expanded in terms of orthogonal functions only symmetric band matrices are involved. Calculation of monoelectronic and bielectronic integrals is described.