Liquid phase parametrisation and solidification in many-body dissipative particle dynamics

TL;DR

This paper systematically investigates many-body dissipative particle dynamics (MDPD), revealing its ability to model liquid, gas, and solid phases, and proposes a protocol for parametrizing real liquids based on its properties.

Contribution

It introduces a systematic study of MDPD's phase behavior and develops a parametrisation protocol for real liquids, expanding its applicability.

Findings

MDPD can produce liquid, gas, and solid phases with a bcc lattice.

Density and surface tension depend on interaction parameters.

A top-down parametrisation protocol for real liquids is devised.

Abstract

Many-body dissipative particle dynamics (MDPD) is a mesoscale method capable of reproducing liquid-vapour coexistence in a single simulation. Despite having been introduced more than a decade ago, this method remains broadly unexplored and, as a result, relatively unused for modelling of industrially important soft matter systems. In this work, we systematically investigate the structure and properties of an MDPD fluid. We show that, besides the liquid phase, the MDPD potential can also yield a gas phase and a thermodynamically stable solid phase with a bcc lattice, but lacking a proper stress-strain relation. For the liquid phase, we determine the dependence of density and surface tension on the interaction parameters, and devise a top-down parametrisation protocol for real liquids.