Structural and dynamical properties of liquid Cu(80)Si(20) alloy studied experimentally and by ab initio molecular dynamics simulations

TitleStructural and dynamical properties of liquid Cu(80)Si(20) alloy studied experimentally and by ab initio molecular dynamics simulations
Publication TypeJournal Article
Year of Publication2011
AuthorsWu S, Kramer MJ, Fang XW, Wang SY, Wang CZ, Ho KM, Ding ZJ, Chen LY
Journal TitlePhysical Review B
Volume84
Pages134208
Date Published10
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberWOS:000296372300006
Keywordscopper, diffraction, transition-metals
Abstract

The local structures and dynamical properties of the liquid Cu(80)Si(20) alloy have been studied by x-ray diffraction and ab initio molecular dynamics (MD) simulations. The pair-correlation functions and the structure factors derived from the three-dimensional coordinates of the MD configurations agree well with the experimental results. The local structure of the liquids is analyzed using Honeycutt-Andersen (HA) indices, Voronoi tessellation (VT), and an atomic cluster-alignment method. The HA indices analysis shows that the pentagonal bipyramid, a fragment of an icosahedron (ICO), plays a dominant role in the short-range order (SRO) of the Cu(80)Si(20) liquid. The HA indices corresponding to the pentagonal bipyramid increase dramatically with decreasing temperature. VT analysis indicates that, while the liquid does exhibit a strong icosahedral SRO, fcc-like SRO is also measurable. The results from VT analysis are further confirmed using the recently developed atomic cluster-alignment method. Finally, self-diffusion constants, as a function of temperature for both Cu and Si species, are calculated.

DOI10.1103/PhysRevB.84.134208
Alternate JournalPhys. Rev. B