Size-asymmetrical Lennard-Jones solid solutions: Interstitials and substitutions

作者:Guo Ziwei; Kindt James T*
来源:Journal of Chemical Physics, 2018, 148(16): 164504.
DOI:10.1063/1.5024230

摘要

We present simulation studies of solid solutions formed upon compression of mixtures of Lennard-Jones particles with diameter ratios 2:1 and 3:1. Grand canonical Monte Carlo (GCMC) and Gibbs-Duhem integration were used to determine the compositions of coexisting solid and liquid phases at several pressures and fixed temperature. Concentrations of small particles dissolved in interstitial sites of the large-particle lattice, under liquid-solid coexistence conditions, were determined directly from GCMC simulations. Indirect methods were used to calculate levels of small particles dissolved substitutionally, either singly or in plural, with the average number of small solutes occupying a lattice site vacated by a large particle increasing with higher pressure. In the cases studied, the fraction of small solutes occupying these substitutional sites was found to be small (2% or lower, depending on the mixture and conditions), but to stay roughly constant with increasing pressure. Structural and dynamic characteristics of the solid solutions are described and compared with reported characteristics of the related interstitial solid solution formed by hard spheres. Published by AIP Publishing.

  • 出版日期2018-4-28

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