Chapter 6 - Van der waals molecules

Abstract

This chapter describes the electrostatic model for Van der Waals complexes. This model has two important features that distinguish it from its predecessors. First, the electric charge distribution of each monomer was described by a set of point multipoles located on atoms and at bond centers, with values determined by the distributed multipole analysis (DMA) of the ab initio wave function. The DMA has the advantage of providing a faithful description of the ab initio charge distribution and its departures from local spherical symmetry. The second key feature of the model was that the atom multipoles were embedded in the hard spheres of appropriate Van der Waals radii centered on nuclei. Thus, the electrostatic model, with its inherent (nonempirical) notion of molecular shape and its accurate representation of the ab initio charge distribution, was constructed for each monomer. Electrostatic models are beginning to make incursions into the field of molecular recognition.