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arXiv · 1211.0718

Low-Energy Polymeric Phases of Alanates

Tran Doan Huan·Maximilian Amsler·Miguel A. L. Marques·Silvana Botti·Alexander Willand·Stefan Goedecker
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Abstract

Low-energy structures of alanates are currently known to be described by patterns of isolated, nearly ideal tetrahedral [AlH$_4$] anions and metal cations. We discover that the novel polymeric motif recently proposed for LiAlH$_4$ plays a dominant role in a series of alanates, including LiAlH$_4$, NaAlH$_4$, KAlH$_4$, Mg(AlH$_4$)$_2$, Ca(AlH$_4$)$_2$ and Sr(AlH$_4$)$_2$. In particular, most of the low-energy structures discovered for the whole series are characterized by networks of corner-sharing [AlH$_6$] octahedra, forming wires and/or planes throughout the materials. Finally, for Mg(AlH$_4$)$_2$ and Sr(AlH$_4$)$_2$, we identify two polymeric phases to be lowest in energy at low temperatures.

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Tran Doan Huan, Maximilian Amsler, Miguel A. L. Marques, Silvana Botti, Alexander Willand, Stefan Goedecker. 2013-03-27. Low-Energy Polymeric Phases of Alanates. https://doi.org/10.1103/physrevlett.110.135502

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