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DOE OSTI · 1296836

Materials Data on BaCaI4 by Materials Project

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Abstract

BaCaI4 is beta Vanadium nitride-derived structured and crystallizes in the triclinic P1 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 46–53°. There are a spread of Ba–I bond distances ranging from 3.44–3.52 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 46–53°. There are a spread of Ca–I bond distances ranging from 3.16–3.23 Å. There are four 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 T-shaped geometry to two equivalent Ba2+ and one Ca2+ atom. In the third I1- site, I1- is bonded in a distorted trigonal planar geometry to one Ba2+ and two equivalent Ca2+ atoms. In the fourth I1- site, I1- is bonded in a distorted trigonal planar geometry to one Ba2+ and two equivalent Ca2+ atoms.

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36 MATERIALS SCIENCEBa-Ca-IBaCaI4crystal structure

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2020-07-22. Materials Data on BaCaI4 by Materials Project. https://doi.org/10.17188/1296836

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