Publication Date:
2016-01-13
Description:
Author(s): Yinwei Li, Lin Wang, Hanyu Liu, Yunwei Zhang, Jian Hao, Chris J. Pickard, Joseph R. Nelson, Richard J. Needs, Wentao Li, Yanwei Huang, Ion Errea, Matteo Calandra, Francesco Mauri, and Yanming Ma Hydrogen sulfides have recently received a great deal of interest due to the record high- T c of up to 203 K observed on strong compression of H 2 S . In this paper, a joint theoretical and experimental study is presented to characterize the dissociation products of compressed H 2 S , which is essential to understand its complex superconducting states. Based on the results here, the authors found H 2 S partially decomposes into S + H 3 S + H 4 S 3 above 27 GPa, and H 4 S 3 emerges as the major component at around 66 GPa. Interestingly, x-ray diffraction (XRD) experiments observed a small fraction of H 3 S and residual H 2 S at least up to 140 GPa, which are believed to be responsible for the two superconducting states observed in experiments. This paper provides the first XRD evidence on the existence of H 3 S at high pressure from the decomposition of H 2 S. [Phys. Rev. B 93, 020103(R)] Published Mon Jan 11, 2016
Keywords:
Structure, structural phase transitions, mechanical properties, defects
Print ISSN:
1098-0121
Electronic ISSN:
1095-3795
Topics:
Physics
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