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arXiv · 2112.11571

The Phonon Quasiparticle Approach for Anharmonic Properties of Solids

Zhen Zhang·Dong-Bo Zhang·Tao Sun·Renata M. Wentzcovitch
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Abstract

Knowledge of lattice anharmonicity is essential to elucidate distinctive thermal properties in crystalline solids. Yet, accurate \textit{ab initio} investigations of lattice anharmonicity encounter difficulties owing to the cumbersome computations. Here we introduce the phonon quasiparticle approach and review its application to various materials. This method efficiently and reliably addresses lattice anharmonicity by combining \textit{ab initio} molecular dynamics and lattice dynamics calculations. Thus, in principle, it accounts for full anharmonic effects and overcomes finite-size effects typical of \textit{ab initio} molecular dynamics. The validity and effectiveness of the current approach are demonstrated in the computation of thermodynamic and heat transport properties of weakly and strongly anharmonic systems.

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Zhen Zhang, Dong-Bo Zhang, Tao Sun, Renata M. Wentzcovitch. 2021-12-21. The Phonon Quasiparticle Approach for Anharmonic Properties of Solids. https://doi.org/10.1088/1742-6596%2F2207%2F1%2F012042

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