Lattice-switch Monte Carlo: the fcc—bcc problem

26th IUPAP Conference on Computational Physics

物理学;计算机科学

Underwood, T.L.^1 ; Ackland, G.J.^1

School of Physics and Astronomy, SUPA, University of Edinburgh, Edinburgh

EH9 3JZ, United Kingdom^1

关键词: Bain orientation;    Fluid-phase;    Free-energy difference;    ITS applications;    Lattice switch Monte Carlo;    Lennard-Jones systems;    Metastable solids;    Solid phasis;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/640/1/012030/pdf
DOI  :  10.1088/1742-6596/640/1/012030

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

Lattice-switch Monte Carlo is an efficient method for calculating the free energy difference between two solid phases, or a solid and a fluid phase. Here, we provide a brief introduction to the method, and list its applications since its inception. We then describe a lattice switch for the fcc and bcc phases based on the Bain orientation relationship. Finally, we present preliminary results regarding our application of the method to the fcc and bcc phases in the Lennard-Jones system. Our initial calculations reveal that the bcc phase is unstable, quickly degenerating into some as yet undetermined metastable solid phase. This renders conventional lattice-switch Monte Carlo intractable for this phase. Possible solutions to this problem are discussed.