Structure and Dynamics of Perovskite Hydrides: AMgH3, A=Na,K,Rb

Journal Article · Mon Jan 01 00:00:00 EST 2007 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.76.214118· OSTI ID:968240

Fornari, M. ^[1]; Subedi, Alaska P ^[2]; Singh, David J ^[2]

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1. Central Michigan University, Mt. Pleasant
2. ORNL

We report density functional studies of the structure and dynamics of NaMgH{sub 3}, KMgH{sub 3}, and RbMgH{sub 3} in the cubic perovskite structure as well as the corresponding fluorides and the alloy (Na,Li)MgH{sub 3}. The hydrides are ionic materials with structural properties very similar to fluorides. However, even though the structures of the hydrides and fluorides are very similar, we find that the dynamics can be quite different. We ascribe these differences to breathing of the hydride ion. This is also reflected in a reduced tendency toward Li off-centering in (Na,Li)MgH{sub 3}.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 968240
• Journal Information: Physical Review B, Vol. 76, Issue 21; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
FLUORIDES
DENSITY FUNCTIONAL METHOD
PEROVSKITES
CUBIC LATTICES
DYNAMICS
MAGNESIUM HYDRIDES
SODIUM HYDRIDES
POTASSIUM HYDRIDES
RUBIDIUM HYDRIDES
LITHIUM HYDRIDES