BONDING IN SMALL DIATOMIC-MOLECULES - AN ANALYSIS USING SIMPLIFIED GROUP-FUNCTION (SGF) THEORY

Simplified group function (SGF) theory is used to analyse the energeti c contributions to the interatomic potentials of the diatomics H-2(+), H-2, He-2(+) and He-2. These species, which contain one, two, three a nd four electrons respectively, range from the strongly (H-2) to the w eakly (He-2) bonded chemical entities. SGF theory provides a simple co nceptual model of the processes occurring during chemical bonding, and the results obtained in this work may be generalized so as to explain the bonding in larger, more complex systems. The relative merits of t he perturbational and variational approaches and of the Lowdin and Gra m-Schmidt orthogonalization procedures are discussed.