Molecular electrostatics. A comprehensive topographical approach

Abstract

An integrated approach to the study of molecular electrostatics is presented. Efficient sequential and parallel algorithms are developed for the computation of the molecular electrostatic potential (MESP) and the molecular electrostatic field (MEF) along with the MEF gradient at a given set of points. Strict bounds for MESP and MEF are used for enhancing the power of the program by virtue of rigorous elimination of numerically insignificant integrals. Recent studies have highlighted the features and utility of MESP topography (in terms of its critical points) in chemistry. An algorithm for locating the critical points (CPs) is described. Some CPs of the MESP for test molecules (viz. C₄H₆, ClO^-₃, P₄S₃ and [V₁₀O₂₈]^6-) are located and characterized in terms of the eigenvalues of the respective Hessians. A rapid yet accurate characterization of the MESP topography is seen to be possible with this approach.