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DOE OSTI · 1289117

Materials Data on Ba2CaI6 by Materials Project

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Abstract

Ba2CaI6 is Hydrophilite-derived structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Ba2+ is bonded to six I1- atoms to form BaI6 octahedra that share corners with four equivalent BaI6 octahedra, corners with four equivalent CaI6 octahedra, an edgeedge with one BaI6 octahedra, and an edgeedge with one CaI6 octahedra. The corner-sharing octahedra tilt angles range from 46–55°. There are two shorter (3.47 Å) and four longer (3.48 Å) Ba–I bond lengths. Ca2+ is bonded to six I1- atoms to form CaI6 octahedra that share corners with eight equivalent BaI6 octahedra and edges with two equivalent BaI6 octahedra. The corner-sharing octahedra tilt angles range from 46–47°. There are four shorter (3.17 Å) and two longer (3.20 Å) Ca–I bond lengths. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and one Ca2+ atom. 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-IBa2CaI6crystal structure

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2020-04-30. Materials Data on Ba2CaI6 by Materials Project. https://doi.org/10.17188/1289117

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