Molecular dynamics study on the liquid phosphorus tribromide by applying force-fields derived from quantum chemical approach

Abstract

The purpose of this paper is to study the molecular dynamics simulation of phosphorus tribromide (PBr3) as the condensed inorganic liquid. To this aim, four regional intermolecular potential functions of phosphorus tribromide in the gas phase were considered. The potential energy data of 9 phosphorous tribromide configuration dimers were calculated at the B3LYP/6-31+G (d) level of theory. The calculated potential data were employed to construct a 4-site all-atom force field model. Then, the force field parameters were used to perform the molecular dynamics simulations and compared the simulation results with experimental data. Quantitative agreements for the atomic number density, internal energy, enthalpy, heat capacity and radial distribution function over a wide range of experimental conditions were obtained as a consequence of the parameters force field validation without using experimental data a priori.