Comparison of the AMBER, CHARMM, COMPASS, GROMOS, OPLS, TraPPE and UFF force fields for prediction of vapor–liquid coexistence curves and liquid densities

Abstract

Monte Carlo simulations in the isobaric–isothermal and Gibbs ensembles are used to compute liquid densities and vapor–liquid coexistence curves for a series of small organic molecules for the AMBER-96, CHARMM22, COMPASS, GROMOS 43A1, OPLS-aa, TraPPE-UA, and UFF force fields. The simulation results are compared with experimental measurements to provide an assessment of the accuracy expected when using these force fields to study unknown molecules.