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arXiv · 2212.14349

Comparative analysis for the behavior of beryllium and magnesium crystals at ultrahigh pressures

N. A. Smirnov
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Abstract

The paper presents ab initio results on the structural phase stability of beryllium and magnesium crystals under high and ultrahigh pressures (multi-terapascal regime). Magnesium is shown to undergo a number of structural transformations which markedly reduce the crystal packing factor. As for beryllium, its high-pressure body-centered cubic phase remains stable even under ultrahigh pressures. Changes in the electronic structure of Be and Mg crystals under compression are analyzed and some interesting effects are revealed. Specifically, a narrow band gap appears in the electronic structure of magnesium under pressures above 2.5 TPa. For the metals of interest, PT-diagrams are constructed and compared with available experimental and theoretical results from other investigations.

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N. A. Smirnov. 2022-12-29. Comparative analysis for the behavior of beryllium and magnesium crystals at ultrahigh pressures. https://doi.org/10.1002/pssb.202300551

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