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Transformation Pathways of Silica under High Pressure

Liping Huang·Murat Durandurdu·John Kieffer
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Abstract

Concurrent molecular dynamics simulations and ab initio calculations show that densification of silica under pressure follows a ubiquitous two-stage mechanism. First, anions form a close-packed sub-lattice, governed by the strong repulsion between them. Next, cations redistribute onto the interstices. In cristobalite silica, the first stage is manifest by the formation of a metastable phase, which was observed experimentally a decade ago, but never indexed due to ambiguous diffraction patterns. Our simulations conclusively reveal its structure and its role in the densification of silica.

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Liping Huang, Murat Durandurdu, John Kieffer. 2006-02-12. Transformation Pathways of Silica under High Pressure. https://doi.org/10.1038/nmat1760

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