One-electron charge transfer states in the theory of strong orthogonal group functions and the barrier in ethane

Abstract

Explicit formulae have been given for the reduced transition density matrices involving one-electron transfer between n two-electron groups described by general singlet strong-orthogonal geminals. The application of these formulae to a complete ab initio calculation of the ethane barrier shows that the variational introduction of a small amount of one-electron CTS within the GF scheme restores the correct order of magnitude of the barrier.