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DOE OSTI · 1199676

Materials Data on Mg(AlH4)2 by Materials Project

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Abstract

Mg(AlH4)2 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Mg(AlH4)2 sheet oriented in the (0, 0, 1) direction. Mg2+ is bonded to six equivalent H1- atoms to form MgH6 octahedra that share corners with six equivalent AlH4 tetrahedra. All Mg–H bond lengths are 1.90 Å. Al3+ is bonded to four H1- atoms to form AlH4 tetrahedra that share corners with three equivalent MgH6 octahedra. The corner-sharing octahedral tilt angles are 14°. There is one shorter (1.60 Å) and three longer (1.63 Å) Al–H bond length. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded in a linear geometry to one Mg2+ and one Al3+ atom. In the second H1- site, H1- is bonded in a single-bond geometry to one Al3+ atom.

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36 MATERIALS SCIENCEAl-H-Mgcrystal structureMg(AlH4)2

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2020-07-15. Materials Data on Mg(AlH4)2 by Materials Project. https://doi.org/10.17188/1199676

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