Iron pentahydride

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Iron pentahydride
3D model (JSmol)
  • InChI=1S/Fe.5H
  • [Fe].[H].[H].[H].[H].[H]
Molar mass 60.885 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Iron pentahydride FeH5 is a superhydride compound of iron and hydrogen, stable under high pressures. It is important because it contains atomic hydrogen atoms that are not bonded into smaller molecular clusters, and may be a superconductor. Pairs of hydrogen atoms are not bonded together into molecules. FeH5 has been made by compressing a flake of iron with hydrogen in a diamond anvil cell to a pressure of 130 GPa and heating to below 1500K. [1] When decompressed to 66 GPa it decomposes to solid FeH3.

The unit cell is tetragonal with space group I4/mmm. [2]

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  1. Pépin, C. M.; Geneste, G.; Dewaele, A.; Mezouar, M.; Loubeyre, P. (28 July 2017). "Synthesis of FeH5: A layered structure with atomic hydrogen slabs". Science. 357 (6349): 382–385. Bibcode:2017Sci...357..382P. doi: 10.1126/science.aan0961 . ISSN   0036-8075. PMID   28751605.
  2. "Synthesis of FeH5 under pressure: Dense atomic metal hydrogen stabilised with Fe". Spotlight on Science. European Synchrotron Radiation Facility. 27 July 2017.