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arXiv · 2310.04754

ScaleLat: A chemical structure matching algorithm for mapping atomic structure of multi-phase system and high entropy alloys

Abstract

ScaleLat (Scale Lattice) is a computer program written in C for performing the atomic structure analysis of multi-phase system or high entropy alloys (HEAs). The program implements an atomic cluster extraction algorithm to obtain all independent and symmetry-reduced characteristic chemical structures for the complex atomic configurations which are usually obtained from molecular dynamics or kinetic Monte-Carlo simulations for supercell containing more than 104 atoms. ScaleLat employes an efficient and unique chemical structure matching algorithm to map all extracted atomic clusters from a large supercell (>10^4 atoms) to a representative small one (~ 10^3 or less), providing the possibility to directly use the highly accurate quantum mechanical methods to study the electronic, magnetic, and mechanical properties of multi-component alloys with complex microstructures. We demonstrate the capability of ScaleLat code by conducting both the atomic structure analysis and chemical structure matching procedure for Fe-12.8 at.% Cr binary alloy and equiatomic CrFeCoNiCu high entropy alloy, and by successfully obtaining the representatively supercells containing 10^2~10^3 atoms of the two alloys. Overall, ScaleLat program provides a universal platform to efficiently project all essential chemical structures of large complex atomic structures to a relatively easy-handling small supercell for quantum mechanical calculations of various user interested properties.

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Nan Li, Junming Guo, Sateng Li, Haoliang Liu, Qianwu Li, Fangjie Shi, Yefei Li, Bing Xiao. 2023-10-07. ScaleLat: A chemical structure matching algorithm for mapping atomic structure of multi-phase system and high entropy alloys. https://arxiv.org/abs/2310.04754

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