TITLE

Hydrogen site energetics in LaNi5Hn and LaCo5Hn: Toward predicting hydrides

AUTHOR(S)
Herbst, J.F.; Hector, L.G.
PUB. DATE
October 2004
SOURCE
Applied Physics Letters;10/18/2004, Vol. 85 Issue 16, p3465
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We have investigated the energetics of hydrogen site occupation in LaNi5Hn (hexagonal P63mc structure) and LaCo5Hn (orthorhombic Cmmm structure) via calculation of the site-dependent enthalpies of hydride formation ΔH. For each structure ΔH was determined for a broad variety of hydrogen configurations. In LaNi5Hn (LaCo5Hn) we find that the minimum ΔH occurs for hydrogen filling of the 2b6c16c2 (4e4h) sites, precisely those identified by neutron diffraction. Hydrogen-richer hydrides are predicted for both structures, in qualitative agreement with experiments performed at higher pressures.
ACCESSION #
14803325

 

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