The valence-bond scf (VB SCF) method.: Synopsis of theory and test calculation of oh potential energy curve

Abstract It is shown how the orbitals in a completely general multi-structure valence-bond wavefunction may be optimised, using the generalised Brillouin theorem. The resulting VB SCF method is a powerful generalisation of the MC SCF method, to permit the use of non-orthogonal orbitals. Some test calculations on OH are reported.