A cluster Monte Carlo method for the simulation of anisotropic systems

Abstract

A Monte Carlo method for studying anisotropic systems with a new type of boundary conditions is proposed. The missing interactions at the sample box surface are replaced by interactions with ghost molecules. The orientations of these ghost particles are sampled from a ‘‘least biased’’ singlet distribution obtained self‐consistently from the order parameter inside the sample. The method is tested on the Lebwohl–Lasher model with 125 and 1000 particles. Results for the transition temperature and order parameters are in good agreement with those obtained from simulation of much larger systems. The method is fairly general and should be applicable in a variety of simulations. Here we show that it can also be used to study director fluctuations in nematogen models.