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arXiv · 1511.05173

Charge density wave in hydrogen at high pressure

Ioan B. Magdau·Graeme J. Ackland
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Abstract

We present extensive molecular dynamics (MD) simulations investigating numerous candidate crystal structures for hydrogen in conditions around the present experimental frontier (400GPa). Spontaneous phase transitions in the simulations reveal a new structure candidate comprising twofold coordinated chains of hydrogen atoms. We explain the electronic structure of this phase in terms of a charge density wave and calculate its experimental signature. In detailed tests of the accuracy of our calculation, we find that k-point sampling is far more important in MD than in static calculations, because of the freedom it give the atoms to rearrange themselves optimally for the given sampling.

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Ioan B. Magdau, Graeme J. Ackland. 2015-11-16. Charge density wave in hydrogen at high pressure. https://arxiv.org/abs/1511.05173

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