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Title: Inelastic neutron scattering evidence for anomalous H–H distances in metal hydrides
Hydrogen-containing materials are of fundamental as well as technological interest. An outstanding question for both is the amount of hydrogen that can be incorporated in such materials, because that determines dramatically their physical properties such as electronic and crystalline structure. The number of hydrogen atoms in a metal is controlled by the interaction of hydrogens with the metal and by the hydrogen–hydrogen interactions. It is well established that the minimal possible hydrogen–hydrogen distances in conventional metal hydrides are around 2.1 Å under ambient conditions, although closer H–H distances are possible for materials under high pressure. We present inelastic neutron scattering measurements on hydrogen in Z r V 2 H x showing nonexpected scattering at low-energy transfer. The analysis of the spectra reveals that these spectral features in part originate from hydrogen vibrations confined by neighboring hydrogen at distances as short as 1.6 Å. These distances are much smaller than those found in related hydrides, thereby violating the so-called Switendick criterion. The results have implications for the design and creation of hydrides with additional properties and applications.  more » « less
Award ID(s):
1933622
PAR ID:
10191662
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
117
Issue:
8
ISSN:
0027-8424
Page Range / eLocation ID:
4021 to 4026
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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