A Monte Carlo approach to chemical bonding in condensed phases

Abstract

Chemical bonding can be markedly affected by a condensed phase environment. This arises from a solvent induced electron–electron attraction. This effect can be taken into account using path integral techniques. The problems that face usual path integral approaches arising from the antisymmetry of the wave functions are ameliorated by performing the path sum with intermediate states that are already antisymmetric. The path sums are evaluated via a Monte Carlo method. Because of the use of a discrete basis this is the path integral analog of a configuration interaction calculation including the influence of the solvent. Illustrative calculations for the dissociation curves of H2 in model environments are shown, illustrating the possibility of dissociation to ions characteristic of condensed phase potential curves.