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arXiv · 0907.2128

Formation of transition metal hydrides at high pressures

Olga Degtyareva·John E. Proctor·Christophe Guillaume·Eugene Gregoryanz·Michael Hanfland
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Abstract

Silane (SiH4) is found to (partially) decompose at pressures above 50 GPa at room temperature into pure Si and H2. The released hydrogen reacts with surrounding metals in the diamond anvil cell to form metal hydrides. A formation of rhenium hydride is observed after the decomposition of silane. From the data of a previous experimental report (Eremets et al., Science 319, 1506 (2008)), the claimed high-pressure metallic and superconducting phase of silane is identified as platinum hydride, that forms after the decomposition of silane. These observations show the importance of taking into account possible chemical reactions that are often neglected in high-pressure experiments.

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Olga Degtyareva, John E. Proctor, Christophe Guillaume, Eugene Gregoryanz, Michael Hanfland. 2009-07-13. Formation of transition metal hydrides at high pressures. https://doi.org/10.1016/j.ssc.2009.07.022

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