Boolean Scheme for Programming Trial Moves That Involve Molecule Insertion and Removal in Monte Carlo Simulation

Abstract

A Boolean scheme is presented for programming trial moves that involve molecule insertion and removal in both grand canonical (GCMC) and Gibbs ensemble (GEMC) Monte Carlo simulation methods. The Boolean scheme makes use of logical data type arrays for keeping track of molecules being inserted and removed, instead of the integer index array technique of the traditional Nicholson's scheme. An exploratory evaluation of the relative computational performance of the two schemes is presented. For GCMC simulation of simple fluids, Nicholson's scheme appears to be more efficient than the Boolean scheme. In contrast, for GEMC simulation of vapor-liquid equilibria (VLE) in binary systems, the Boolean scheme seems to become more efficient as the complexity of the intermolecular potential increases. However, considering the limitations intrinsic to any evaluation of computational performance, the two schemes should be regarded as alternative tools to be tried for the particular application of interest to the user.

Keywords:

• Simulation Methodology
• Monte Carlo Simulation
• Grand Canonical Ensemble
• Gibbs Ensemble
• Trial Moves
• Insertion And Removal