Pressure induced Hydrogen-Hydrogen interaction in metallic FeH revealed by NMR

Abstract

Knowledge of the behavior of hydrogen in metal hydrides is the key for understanding their electronic properties. So far, no experimental methods exist to access these properties beyond 100 GPa, where high-Tc superconductivity emerges. Here, we present an 1H-NMR study of cubic FeH up to 200GPa. We observe a distinct deviation from the ideal metallic behavior between 64 and 110 GPa that suggests pressure-induced H-H interactions. Accompanying ab-initio calculations support this interpretation, as they reveal the formation of an intercalating sublattice of electron density, which enhances the hydrogen contribution to the electronic density of states at the Fermi level. This study shows that pressure induced H-H interactions can occur in metal hydrides at much lower compression and larger H-H distances than previously thought and stimulates an alternative pathway in the search for novel high-temperature superconductors.

arXiv comment19 pages, 8 figures

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Cited by in corpus (5)

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• In-situ High Pressure Nuclear Magnetic Resonance Crystallography
• Improving Resolution of Solid State NMR in Dense Molecular Hydrogen
• Table-top NMR system for high-pressure studies with in-situ laser heating
• Transmission of radio-frequency waves and nuclear magnetic resonance in lanthanum superhydrides