HFF: a force field for liquid crystal molecules

Abstract

Soft material simulations require an accurate representation of the intermolecular and intramolecular potential energy surface in order to achieve realistic predictions for their properties. The conformational potential of the molecules has a profound effect on many properties of molecular aggregates. This is usually a serious weakness of most commercial empirical force fields. In this paper we describe a force field (HFF), specifically designed for liquid crystal molecules. Intramolecular parameters are obtained from ab initio quantum mechanics calculations on model molecules which are substructures of liquid crystal molecules. HFF reproduces ab initio conformational energy profiles for model molecules with errors much smaller than commercial force fields. Our focus is not on creating general purpose force fields but on strategies to develop reliable force fields on-demand for specific needs.