Coupling between Nuclear and Electronic Motion in Diatomic Molecules

Abstract

The paper presents a general theory of the coupling between nuclear and electronic motion in diatomic molecules. Special consideration is given to the case of large nuclear separation. It is shown that, for large separation of the nuclei, the electronic—nuclear coupling terms are of the order of the isotope effect. The physical meaning of an (R−2)-dependent potential, which was found by Dalgarno and McCarroll, is explained as a centrifugal effect associated with a certain rotation of the electrons within the atoms. It is not significant at large separations.