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DOE OSTI · 1576908

Compressive sensing lattice dynamics. II. Efficient phonon calculations and long-range interactions

Abstract

We apply the compressive sensing lattice dynamics method to calculate phonon dispersion for crystalline solids. While existing methods such as frozen phonon, small displacement, and linear response are routinely applied for phonon calculations, they are considerably more expensive or cumbersome to apply to certain solids, including structures with large unit cells or low symmetry, systems that require more expensive electronic structure treatment, and polar semiconductors/insulators. In the latter case, we propose an approach based on a corrected long-range force constant model with proper treatment of the acoustic sum rule and the symmetric on-site force constant matrix. Here, our approach is demonstrated to be accurate and efficient for these systems through case studies of NaCl, CeO 2 , Y 3 Al 5 O 12 , and La 2 Fe 14 B.

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BibTeXRIS

Zhou, Fei, Sadigh, Babak, Åberg, Daniel, Xia, Yi, Ozoliņš, Vidvuds. 2019-11-20. Compressive sensing lattice dynamics. II. Efficient phonon calculations and long-range interactions. https://doi.org/10.1103/physrevb.100.184309

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36 MATERIALS SCIENCE↗