Ab initio studies of non-bonded hydrocarbon potentials

Abstract
Results are reported of ab initio molecular orbital calculations of the energies of interaction of hydrogen and methane molecules. The aim in the former case is to provide a detailed analysis of the short range repulsive potential for this interaction, an interaction which is also relevant to the general field of hydrocarbon potentials, while the second set of calculations are intended to provide guidance as to models and parameters for saturated hydrocarbons. The results suggest that the repulsive interactions between bonds containing hydrogen may be adequately described by an isotropic interaction between centres located along the internuclear axis of the bond; and that the use of a larger number of parameters in atom–atom models may be unnecessary.