Synthesis and stability of hydrogen selenide compounds at high pressure

Edward J. Pace, Jack Binns, Miriam Pena Alvarez, Philip Dalladay-Simpson, Eugene Gregoryanz, Ross T. Howie*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

The observation of high-temperature superconductivity in hydride sulfide (H2S) at high pressures has generated considerable interest in compressed hydrogen-rich compounds. High-pressure hydrogen selenide (H2Se) has also been predicted to be superconducting at high temperatures; however, its behaviour and stability upon compression remains unknown. In this study, we synthesize H2Se in situ from elemental Se and molecular H-2 at pressures of 0.4 GPa and temperatures of 473 K. On compression at 300 K, we observe the high-pressure solid phase sequence (I-I'-IV) of H2Se through Raman spectroscopy and x-ray diffraction measurements, before dissociation into its constituent elements. Through the compression of H2Se in H-2 media, we also observe the formation of a host-guest structure, (H2Se)(2)H-2, which is stable at the same conditions as H2Se, with respect to decomposition. These measurements show that the behaviour of H2Se is remarkably similar to that of H2S and provides further understanding of the hydrogen chalcogenides under pressure. Published by AIP Publishing.

Original languageEnglish
Article number184303
Number of pages5
JournalThe Journal of Chemical Physics
Volume147
Issue number18
DOIs
Publication statusPublished - 13 Nov 2017

Keywords

  • X-RAY-DIFFRACTION
  • RAMAN-SPECTROSCOPY
  • PHASE-TRANSITIONS
  • CRYSTAL-STRUCTURE
  • SULFUR HYDRIDE
  • SULFIDE
  • H2S
  • SUPERCONDUCTIVITY
  • SYSTEM
  • DISSOCIATION

Fingerprint

Dive into the research topics of 'Synthesis and stability of hydrogen selenide compounds at high pressure'. Together they form a unique fingerprint.

Cite this