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DOE OSTI · 1205423

Materials Data on KAlH4 by Materials Project

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Abstract

KAlH4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six H1- atoms. There are a spread of K–H bond distances ranging from 2.66–2.89 Å. Al3+ is bonded in a tetrahedral geometry to four H1- atoms. There is two shorter (1.63 Å) and two longer (1.64 Å) Al–H bond length. There are three inequivalent H1- sites. In the first H1- site, H1- is bonded in a distorted single-bond geometry to two equivalent K1+ and one Al3+ atom. In the second H1- site, H1- is bonded in a distorted single-bond geometry to one K1+ and one Al3+ atom. In the third H1- site, H1- is bonded in a distorted linear geometry to one K1+ and one Al3+ atom.

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36 MATERIALS SCIENCEAl-H-Kcrystal structureKAlH4

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2020-07-15. Materials Data on KAlH4 by Materials Project. https://doi.org/10.17188/1205423

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