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DOE OSTI · 1280233

Materials Data on SrMg2FeH8 by Materials Project

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Abstract

SrMg2FeH8 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Sr2+ is bonded to twelve H1- atoms to form SrH12 cuboctahedra that share edges with six equivalent SrH12 cuboctahedra and faces with two equivalent FeH6 octahedra. There are six shorter (2.65 Å) and six longer (2.66 Å) Sr–H bond lengths. Mg2+ is bonded in a 1-coordinate geometry to ten H1- atoms. There are a spread of Mg–H bond distances ranging from 1.92–2.26 Å. Fe2+ is bonded to six equivalent H1- atoms to form FeH6 octahedra that share faces with two equivalent SrH12 cuboctahedra. All Fe–H bond lengths are 1.57 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded in a 1-coordinate geometry to one Sr2+, three equivalent Mg2+, and one Fe2+ atom. In the second H1- site, H1- is bonded in a distorted single-bond geometry to three equivalent Sr2+ and one Mg2+ atom.

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36 MATERIALS SCIENCEcrystal structureFe-H-Mg-SrSrMg2FeH8

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2020-07-16. Materials Data on SrMg2FeH8 by Materials Project. https://doi.org/10.17188/1280233

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