(476a) Predicting Virial Coefficients and Alchemical Transformations By Extrapolating Mayer-Sampling Monte Carlo Simulations

A statistical mechanical extrapolation method is presented which allows a single Mayer-sampling Monte Carlo simulation to predict virial coefficients over a large range of both temperatures and model parameter values (i.e., alchemical transformation) with minimal increase in computational cost [1]. We will show that a simulation of the SPC/E (extended simple point charge) water model at one state point can quantitatively predict the second virial coefficient continuously across three orders of magnitude in temperature change, concomitantly changing by four orders of magnitude in value, with less than a 2% deviation. The same simulation was also used to simultaneously predict the second virial coefficient of a modified SPC/E model with site charges scaled by a constant factor, from an increase of 40% down to zero charge. This method is also shown to perform well for the third virial coefficient and the exponential model parameter for a Lennard-Jones fluid. Example code is provided at https://github.com/usnistgov/mayer-extrapolation.

[1] H.W. Hatch, et al., J. Chem. Phys., 147, 231102 (2017). https://doi.org/10.1063/1.5016165