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arXiv · 1308.0913

Sound velocities of hexagonal close-packed H2 and He under pressure

Yu. A. Freiman·Alexei Grechnev·S. M. Tretyak·A. F. Goncharov·C. -s. Zha·R. J. Hemley
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Abstract

Bulk, shear, and compressional aggregate sound velocities of hydrogen and helium in the close- packed hexagonal structure are calculated over a wide pressure range using two complementary approaches: semi-empirical lattice dynamics based on the many-body intermolecular potentials and density-functional theory in the generalized gradient approximation. The sound velocities are used to calculate pressure dependence of the Debye temperature. The comparison between experiment and first-principle and semi-empirical calculations provide constraints on the density dependence of intermolecular interactions in the zero-temperature limit.

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Yu. A. Freiman, Alexei Grechnev, S. M. Tretyak, A. F. Goncharov, C. -s. Zha, R. J. Hemley. 2013-08-05. Sound velocities of hexagonal close-packed H2 and He under pressure. https://doi.org/10.1103/physrevb.88.214501

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