DL_MONTE: A multipurpose code for Monte Carlo simulation

TL;DR

DL_MONTE is a versatile open-source Monte Carlo simulation software that incorporates advanced methods like free energy calculations, pore confinement, and a Python toolkit, enabling broad applications in molecular simulation.

Contribution

The paper introduces recent key features of DL_MONTE, including new boundary conditions, free energy methods, and a Python toolkit, expanding its capabilities for molecular simulations.

Findings

Applied umbrella sampling to lipid translocation

Used LSMC to study water crystal phases

Demonstrated broad applicability of DL_MONTE methods

Abstract

DL_MONTE is an open source, general-purpose software package for performing Monte Carlo simulations. It includes a wide variety of force fields and MC techniques, and thus is applicable to a broad range of problems in molecular simulation. Here we provide an overview of DL_MONTE, focusing on key features recently added to the package. These include the ability to treat systems confined to a planar pore (i.e. `slit' or `slab' boundary conditions); the lattice-switch Monte Carlo (LSMC) method for evaluating precise free energy differences between competing polymorphs; various commonly-used methods for evaluating free energy profiles along transition pathways (including umbrella sampling, Wang-Landau and transition matrix); and a supplementary Python toolkit for simulation management and application of the histogram reweighting analysis method. We provide two `real world' examples to elucidate the use of these methods in DL_MONTE. In particular, we apply umbrella sampling to calculate the free energy profile associated with the translocation of a lipid through a bilayer. Moreover we employ LSMC to examine the thermodynamic stability of two plastic crystal phases of water at high pressure. Beyond this, we provide instructions on how to access DL_MONTE, and point to additional information valuable to existing and prospective users.