Freezing of Polydisperse Hard Spheres

TL;DR

This study investigates the phase behavior of polydisperse hard spheres through simulations and equations of state, revealing no terminal polydispersity and discussing limitations of previous models.

Contribution

It introduces a new scheme for determining crystalline phase composition in polydisperse fluids and compares simulation results with theoretical assumptions.

Findings

No evidence of terminal polydispersity in fluid phase

Discrepancies with previous simulations are due to modeling limitations

New method for evaluating crystalline phase composition

Abstract

The fluid - crystal equilibria of polydisperse mixtures of hard spheres have been studied by computer simulation of the solid phase and using an accurate equation of state for the fluid. A new scheme has been developed to evaluate the composition of crystalline phases in equilibrium with a given polydisperse fluid. Some common assumptions in theoretical approaches and their results are discussed on the light of the simulation results. Finally, no evidence of the existence of a terminal polydispersity in the fluid phase is found for polydisperse hard spheres, the disagreement of this finding with previous molecular simulation results is explained in terms of the inherent limitations of some ways of modeling the chemical potential as a function of the particle size.