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arXiv · 1205.2290

Strong Isotopic Effect in Phase II of Dense Solid Hydrogen and Deuterium

Grégory Geneste·Marc Torrent·François Bottin·Paul Loubeyre
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Abstract

Quantum nuclear zero-point motions in solid H$_2$ and D$_2$ under pressure are investigated at 80 K up to 160 GPa by first-principles path-integral molecular dynamics calculations. Molecular orientations are well-defined in phase II of D$_2$, while solid H$_2$ exhibits large and very asymmetric angular quantum fluctuations in this phase, with possible rotation in the (bc) plane, making it difficult to associate a well-identified single classical structure. The mechanism for the transition to phase III is also described. Existing structural data support this microscopic interpretation.

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Grégory Geneste, Marc Torrent, François Bottin, Paul Loubeyre. 2012-05-10. Strong Isotopic Effect in Phase II of Dense Solid Hydrogen and Deuterium. https://doi.org/10.1103/physrevlett.109.155303

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