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DOE OSTI · 1289735

Materials Data on SrCa2I6 by Materials Project

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Abstract

SrCa2I6 is Hydrophilite-derived structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Sr2+ is bonded to six I1- atoms to form distorted SrI6 pentagonal pyramids that share corners with four equivalent CaI6 octahedra, edges with two equivalent CaI6 octahedra, and edges with two equivalent SrI6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 40–57°. There are a spread of Sr–I bond distances ranging from 3.26–3.48 Å. Ca2+ is bonded to six I1- atoms to form CaI6 octahedra that share corners with six equivalent CaI6 octahedra, corners with two equivalent SrI6 pentagonal pyramids, an edgeedge with one CaI6 octahedra, and an edgeedge with one SrI6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 45–62°. There are a spread of Ca–I bond distances ranging from 3.04–3.25 Å. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to two equivalent Sr2+ and one Ca2+ atom. In the second I1- site, I1- is bonded in a distorted trigonal planar geometry to one Sr2+ and two equivalent Ca2+ atoms. In the third I1- site, I1- is bonded in a distorted trigonal planar geometry to three equivalent Ca2+ atoms.

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36 MATERIALS SCIENCECa-I-Srcrystal structureSrCa2I6

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2020-07-15. Materials Data on SrCa2I6 by Materials Project. https://doi.org/10.17188/1289735

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