An analytical, variable resolution, complete description of static molecules and their intermolecular binding properties.

A fully analytical description of molecular shape, as defined by the shrink-wrap isodensity or solvent-excluded surfaces and local properties related to Coulomb, donor/acceptor, and polarizability (dispersion) interactions is described. The molecular surface and four local properties adequate for describing intermolecular interactions (the molecular electrostatic potential and the local ionization energy, electron affinity, and polarizability) are fitted to spherical-harmonic expansions, which provide a compact and information-rich description of the properties of the static molecule. The resolution of the description can be varied from isotropic to near atomistic detail by adjusting the order of the individual spherical-harmonic expansions. Examples are given to illustrate the effect of truncating the different spherical-harmonic approximations.