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arXiv · 2508.17977

Ab initio study of anomalous temperature dependence of resistivity in V-Al alloys

Gabor Csire·Oleg E. Peil
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Abstract

V$_{1-x}$Al$_x$ is a representative example of highly resistive metallic alloys exhibiting a crossover to a negative temperature coefficient of resistivity (TCR), known as the Mooij correlation. Despite numerous proposals to explain this anomalous behavior,none have provided a satisfactory quantitative explanation thus far. In this work, we calculate the electrical conductivity using an ab initio methodology that combines the Kubo-Greenwood formalism with the coherent potential approximation (CPA). The temperature dependence of the conductivity is obtained within a CPA-based model of thermal atomic vibrations. Using this approach, we observe the crossover to the negative TCR behavior in V$_{1-x}$Al$_x$, with the temperature coefficient following the Mooij correlation, which matches experimental observations in the intermediate-to-high temperature range. Analysis of the results allows us to clearly identify a non-Boltzmann contribution responsible for this behavior and describe it as a function of temperature and composition.

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Gabor Csire, Oleg E. Peil. 2025-08-25. Ab initio study of anomalous temperature dependence of resistivity in V-Al alloys. https://doi.org/10.1103/qvb6-ymts

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