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arXiv · 1807.03079

Lattice dynamics and thermophysical properties of h.c.p. Os and Ru from the quasi-harmonic approximation

Mauro Palumbo·Andrea Dal Corso
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Abstract

We report first-principles phonon frequencies and anharmonic thermodynamic properties of h.c.p. Os and Ru calculated within the quasi-harmonic approximation, including Gruneisen parameters, temperature-dependent lattice parameters, thermal expansion, and isobaric heat capacity. We discuss the differences between a full treatment of anisotropy and a simplified approach with a constant c/a ratio. The results are systematically compared with the available experimental data and an overall satisfactory agreement is obtained.

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Mauro Palumbo, Andrea Dal Corso. 2018-07-09. Lattice dynamics and thermophysical properties of h.c.p. Os and Ru from the quasi-harmonic approximation. https://doi.org/10.1088/1361-648x%2Faa7dca

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