Determining pressure-temperature phase diagrams of materials

TL;DR

This paper introduces an extended nested sampling algorithm capable of efficiently determining complete pressure-temperature phase diagrams of materials, including solid-solid transitions, with minimal prior knowledge.

Contribution

The authors develop and demonstrate a highly automated nested sampling method for calculating phase diagrams under periodic boundary and constant pressure conditions.

Findings

Successfully applied to Lennard-Jones, aluminium, and NiTi systems.

Revealed solid-solid phase transitions without prior structural information.

Provided a versatile tool for phase diagram prediction in materials science.

Abstract

We extend the nested sampling algorithm to simulate materials under periodic boundary and constant pressure conditions, and show how it can be used to determine the complete equilibrium phase diagram, for a given potential energy function, efficiently and in a highly automated fashion. The only inputs required are the composition and the desired pressure and temperature ranges, in particular, solid-solid phase transitions are recovered without any a priori knowledge about the structure of solid phases. We benchmark and showcase the algorithm on the periodic Lennard-Jones system, aluminium and NiTi.