Optimization of intermolecular interaction potential energy parameters for Monte-Carlo and molecular dynamics simulations

Abstract

Derivation of high-quality intermolecular potentials for molecular dynamics (MD) and Monte Carlo (MC) simulations is crucial for efficient modeling of molecular systems. Despite their overall complexity, the interactions potentials have often been derived in a semiempirical manner, though in certain cases, also ab initio techniques have been involved in their construction. In the present study, we aim to construct optimized intermolecular interaction potentials to be used for MD and MC simulations of pure molecular liquids and their mixtures. We have focused on one of the simplest forms of the potentials, namely the Lennard-Jones (LJ) + Coulomb electrostatic terms. Interaction between each pair of atoms in the molecular liquids has thus been characterized by the LJ parameters + atomic charges. The optimization has been performed by genetic algorithms. An in-depth analysis of the performances of both the standard, widely used (i.e. non-optimized), and the optimized interaction potentials was carried out. This analysis was carried out from various aspects related to their performances. © 2012 Springer-Verlag.