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arXiv · 1911.01526

Beryllium Polyhydride Be4H8(H2)2 Synthesized at HP/HT

Takahiro Matsuoka·Hiroshi Fujihisa·Takahiro Ishikawa·Takaya Nakagawa·Keiji Kuno·Naohisa Hirao·Yasuo Ohishi·Katsuya Shimizu·Shigeo Sasaki
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Abstract

We report the XRD and Raman scattering measurements in combination with DFT calculations that reveal the formation of beryllium polyhydride Be4H8(H2)2 by laser heating Be/H2 mixture to above 1700 K at pressures between 5 GPa and 8 GPa. The Be4H8(H2)2 crystallizes in a P6_3/mmc structure and consists of corner-sharing BeH4 tetrahedrons and H2 molecules that are in an interstitial site. The Be4H8(H2)2 is stable at least to 14 GPa on compression and stable down to 4 GPa at room temperature. Our ab-initio calculations suggest that the Be4H8(H2)2 is a meta-stable phase of Be-H system.

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Takahiro Matsuoka, Hiroshi Fujihisa, Takahiro Ishikawa, Takaya Nakagawa, Keiji Kuno, Naohisa Hirao, Yasuo Ohishi, Katsuya Shimizu, Shigeo Sasaki. 2019-11-04. Beryllium Polyhydride Be4H8(H2)2 Synthesized at HP/HT. https://doi.org/10.1103/physrevmaterials.4.125402

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