A Finite-Size Scaling Study of a Model of Globular Proteins

TL;DR

This study uses advanced Monte Carlo simulations to analyze the phase behavior of a globular protein model, accurately locating the critical point and exploring the metastable coexistence region.

Contribution

It applies finite-size scaling and hyper-parallel tempering methods to determine the critical parameters and phase diagram of a protein-like model, extending previous simulation capabilities.

Findings

Accurate critical point parameters determined.

Phase diagram of metastable fluid-fluid coexistence mapped.

Extended the accessible region near the critical point.

Abstract

Grand canonical Monte Carlo simulations are used to explore the metastable fluid-fluid coexistence curve of the modified Lennard-Jones model of globular proteins of ten Wolde and Frenkel (Science, v277, 1975 (1997)). Using both mixed-field finite-size scaling and histogram reweighting methods, the joint distribution of density and energy fluctuations is analyzed at coexistence to accurately determine the critical-point parameters. The subcritical coexistence region is explored using the recently developed hyper-parallel tempering Monte Carlo simulation method along with histogram reweighting to obtain the density distributions. The phase diagram for the metastable fluid-fluid coexistence curve is calculated in close proximity to the critical point, a region previously unattained by simulation.