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DOE OSTI · 1282098

Materials Data on BaCaI4 by Materials Project

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Abstract

BaCaI4 is Hydrophilite-derived structured and crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Ba2+ is bonded to six I1- atoms to form BaI6 octahedra that share corners with eight equivalent CaI6 octahedra and edges with two equivalent BaI6 octahedra. The corner-sharing octahedra tilt angles range from 38–55°. There are a spread of Ba–I bond distances ranging from 3.43–3.51 Å. Ca2+ is bonded to six I1- atoms to form CaI6 octahedra that share corners with eight equivalent BaI6 octahedra and edges with two equivalent CaI6 octahedra. The corner-sharing octahedra tilt angles range from 38–55°. There are two shorter (3.15 Å) and four longer (3.22 Å) Ca–I bond lengths. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted trigonal planar geometry to one Ba2+ and two equivalent Ca2+ atoms. In the second I1- site, I1- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+ and one Ca2+ atom.

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36 MATERIALS SCIENCEBa-Ca-IBaCaI4crystal structure

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2020-07-15. Materials Data on BaCaI4 by Materials Project. https://doi.org/10.17188/1282098

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