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arXiv · 2512.22370

Thermal Equilibrium Vacancy Concentration in an Alloy with Chemical Short-Range Order

Hao Tang·Hoje Chun·Rafael Gomez-Bombarelli·Yuri Mishin·Ju Li
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Abstract

The equilibrium vacancy concentration in multi-principal element alloys remains a controversial and nontrivial subject, primarily because of chemical complexity and chemical short-range order (CSRO). Here we derive an exact expression that is amenable to atomistic calculations, using multiple perspectives. We applied this expression to equiatomic CrCoNi alloys in the face-centered cubic structure. The derived equilibrium vacancy concentration is used in our recent work, which predicts the chemical short-range order formation timescale consistent with experimental observation. The results demonstrate the practical utility of the approach for predicting equilibrium vacancy concentrations in compositionally complex alloys.

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Hao Tang, Hoje Chun, Rafael Gomez-Bombarelli, Yuri Mishin, Ju Li. 2025-12-26. Thermal Equilibrium Vacancy Concentration in an Alloy with Chemical Short-Range Order. https://arxiv.org/abs/2512.22370

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