Decomposition of solid hydrogen bromide at high pressure

Defang Duan; Fubo Tian; Xiaoli Huang; Da Li; Hongyu Yu; Yunxian Liu; Yanbin Ma; Bingbing Liu; Tian Cui

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arXiv · 1504.01196

Decomposition of solid hydrogen bromide at high pressure

Defang Duan·Fubo Tian·Xiaoli Huang·Da Li·Hongyu Yu·Yunxian Liu·Yanbin Ma·Bingbing Liu·Tian Cui

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Abstract

The stability of different stoichiometric H$_n$Br ($n$=1-7) compounds under pressure are extensively studied using density functional theory calculations. Five new energetically stable stoichiometries of H$_2$Br, H$_3$Br, H$_4$Br, H$_5$Br, and H$_7$Br were uncovered at high pressure. The results show that HBr is stable below 64 GPa, then decomposes into new compound H$_2$Br and Br$_2$ molecular crystal. For H$_2$Br and H$_3$Br compounds, they were found to become stable above 30 GPa and 8 GPa, respectively. In addition, we accidentally discovered the triangular H$_3^+$ species in H$_5$Br compounds at 100 GPa. Further electron-phonon coupling calculations predicted that hydrogen-rich H$_2$Br and H$_4$Br compounds are superconductors with critical temperature of superconductivity $T_c$ of 12.1 K and 2.4 K at 240 GPa, respectively.

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Defang Duan, Fubo Tian, Xiaoli Huang, Da Li, Hongyu Yu, Yunxian Liu, Yanbin Ma, Bingbing Liu, Tian Cui. 2015-04-06. Decomposition of solid hydrogen bromide at high pressure. https://arxiv.org/abs/1504.01196

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