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quasiharmonic equations of state for dynamically-stabilized soft-mode materials

N. D. Drummond·G. J. Ackland
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Abstract

We introduce a method for treating soft modes within the analytical framework of the quasiharmonic equation of state. The corresponding double-well energy-displacement relation is fitted to a functional form that is harmonic in both the low- and high-energy limits. Using density-functional calculations and statistical physics, we apply the quasiharmonic methodology to solid periclase. We predict the existence of a B1--B2 phase transition at high pressures and temperatures.

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BibTeXRIS

N. D. Drummond, G. J. Ackland. 2002-03-29. quasiharmonic equations of state for dynamically-stabilized soft-mode materials. https://doi.org/10.1103/physrevb.65.184104

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