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DOE OSTI · 2477474

A high-throughput framework for lattice dynamics

Abstract

We develop an automated high-throughput workflow for calculating lattice dynamical properties from first principles including those dictated by anharmonicity. The pipeline automatically computes interatomic force constants (IFCs) up to 4th order from perturbed training supercells, and uses the IFCs to calculate lattice thermal conductivity, coefficient of thermal expansion, and vibrational free energy and entropy. It performs phonon renormalization for dynamically unstable compounds to obtain real effective phonon spectra at finite temperatures and calculates the associated free energy corrections. The methods and parameters are chosen to balance computational efficiency and result accuracy, assessed through convergence testing and comparisons with experimental measurements. Deployment of this workflow at a large scale would facilitate materials discovery efforts toward functionalities including thermoelectrics, contact materials, ferroelectrics, aerospace components, as well as general phase diagram construction.

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BibTeXRIS

Zhu, Zhuoying, Park, Junsoo, Sahasrabuddhe, Hrushikesh, Ganose, Alex M., Chang, Rees, Lawson, John W., Jain, Anubhav. 2024-11-14. A high-throughput framework for lattice dynamics. https://doi.org/10.1038/s41524-024-01437-w

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