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DOE OSTI · 1159050

Molecular Solid EOS based on Quasi-Harmonic Oscillator approximation for phonons

Menikoff, Ralph
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Abstract

A complete equation of state (EOS) for a molecular solid is derived utilizing a Helmholtz free energy. Assuming that the solid is nonconducting, phonon excitations dominate the specific heat. Phonons are approximated as independent quasi-harmonic oscillators with vibrational frequencies depending on the specific volume. The model is suitable for calibrating an EOS based on isothermal compression data and infrared/Raman spectroscopy data from high pressure measurements utilizing a diamond anvil cell. In contrast to a Mie-Gruneisen EOS developed for an atomic solid, the specific heat and Gruneisen coefficient depend on both density and temperature.

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97 MATHEMATICS AND COMPUTINGEOSMOLECULAR SOLIDPHONON SPECTRUM

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BibTeXRIS

Menikoff, Ralph. 2014-09-02. Molecular Solid EOS based on Quasi-Harmonic Oscillator approximation for phonons. https://doi.org/10.2172/1159050

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