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The crystal structure and surface energy of NaAlH4: a comparison of DFT methodologies
Terry J Frankcombe1, Ole Martin Løvvik
1Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Abstract:
This paper presents a comparison of the bulk structure, cleavage energies, and local densities of states of solid NaAlH4 calculated using several different density functional theory methodologies. Good agreement is obtained for the bulk crystal structure. Larger differences become apparent for the calculated surface energies and local densities of states. The (001) NaAlH4 surface is clearly identified as the most stable surface, followed by the (112) and (101) surfaces, with the (100) surface being the least stable. We present an analysis of the local density of states of atoms in the exposed NaAlH4 surface.
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