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

Abstract

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}.

Authors:
 [1];  [2];  [2]
  1. Central Michigan University, Mt. Pleasant
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
968240
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 76; Journal Issue: 21
Country of Publication:
United States
Language:
English
Subject:
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

Citation Formats

Fornari, M., Subedi, Alaska P, and Singh, David J. Structure and Dynamics of Perovskite Hydrides: AMgH3, A=Na,K,Rb. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.76.214118.
Fornari, M., Subedi, Alaska P, & Singh, David J. Structure and Dynamics of Perovskite Hydrides: AMgH3, A=Na,K,Rb. United States. doi:10.1103/PhysRevB.76.214118.
Fornari, M., Subedi, Alaska P, and Singh, David J. Mon . "Structure and Dynamics of Perovskite Hydrides: AMgH3, A=Na,K,Rb". United States. doi:10.1103/PhysRevB.76.214118.
@article{osti_968240,
title = {Structure and Dynamics of Perovskite Hydrides: AMgH3, A=Na,K,Rb},
author = {Fornari, M. and Subedi, Alaska P and Singh, David J},
abstractNote = {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}.},
doi = {10.1103/PhysRevB.76.214118},
journal = {Physical Review B},
number = 21,
volume = 76,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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