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arXiv · 1902.11230

Ab initio vibrational free energies including anharmonicity for multicomponent alloys

Blazej Grabowski·Yuji Ikeda·Fritz Körmann·Christoph Freysoldt·Andrew Ian Duff·Alexander Shapeev·Jörg Neugebauer
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Abstract

A density-functional-theory based approach to efficiently compute numerically exact vibrational free energies - including anharmonicity - for chemically complex multicomponent alloys is developed. It is based on a combination of thermodynamic integration and a machine-learning potential. We demonstrate the performance of the approach by computing the anharmonic free energy of the prototypical five-component VNbMoTaW refractory high entropy alloy.

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Blazej Grabowski, Yuji Ikeda, Fritz Körmann, Christoph Freysoldt, Andrew Ian Duff, Alexander Shapeev, Jörg Neugebauer. 2019-02-28. Ab initio vibrational free energies including anharmonicity for multicomponent alloys. https://doi.org/10.1038/s41524-019-0218-8

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