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DOE OSTI · 1289071

Materials Data on BaCaI4 by Materials Project

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Abstract

BaCaI4 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine I1- atoms. There are a spread of Ba–I bond distances ranging from 3.58–4.18 Å. Ca2+ is bonded to six I1- atoms to form corner-sharing CaI6 octahedra. The corner-sharing octahedra tilt angles range from 10–46°. There are a spread of Ca–I bond distances ranging from 3.05–3.18 Å. There are four inequivalent I1- sites. In the first I1- site, I1- is bonded in a T-shaped geometry to one Ba2+ and two equivalent Ca2+ atoms. In the second I1- site, I1- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Ca2+ atoms. In the third I1- site, I1- is bonded in a 1-coordinate geometry to three equivalent Ba2+ and one Ca2+ atom. In the fourth I1- site, I1- is bonded to three equivalent Ba2+ and one Ca2+ atom to form distorted corner-sharing IBa3Ca trigonal pyramids.

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36 MATERIALS SCIENCEBa-Ca-IBaCaI4crystal structure

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2020-05-02. Materials Data on BaCaI4 by Materials Project. https://doi.org/10.17188/1289071

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