The critical role of force-fields in property prediction

The present investigation discusses the treatment of non-bonded interactions in various force-fields and the physical significance of these interactions, with special attention given to the electrostatic interactions. Although molecular geometries are generally well reproduced, calculations of conformational energydifferences and interaction energies vary significantly from one force-field to another. As a test for the reliability of the non-bonded interactions, vapor-liquid equilibrium (VLE) data have been calculated for a small number of systems using three different force-fields. The force-fields used gave results which differedwidely, illustrating that the choice of force-field can be critical for predicting properties in a reliable way.