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arXiv · 2410.09545

A Thermodynamic Constraint for the Electronic Structure of Fe-Ni Alloys at Room And High-Temperature

Jonathan Paras·Antoine Allanore
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Abstract

The measurement of the electronic structure of metal alloys is hampered by the in-applicability of conventional quantum oscillation measurements owing to electron scattering by thermal or alloy disorder. Recent advancements in the study of the electronic contribution to the entropy suggest a path to ground transport properties in alloy equilibrium thermodynamics. Fe-Ni represents an interesting test-case because it exhibits an intricate electronic structure, order-disorder transformations, and a large solid-solution region where equilibrium data can be obtained. Using cluster modeling, the electronic contribution to the entropy can be inferred from high-temperature thermodynamic data. Electronic transport property measurements can be used to independently evaluate the electronic contribution to the entropy. Reconciling these two approaches at high temperature supports this method to study electronic structure for metal alloys.

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Jonathan Paras, Antoine Allanore. 2025-02-06. A Thermodynamic Constraint for the Electronic Structure of Fe-Ni Alloys at Room And High-Temperature. https://doi.org/10.1103/physrevb.111.085105

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