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DOE OSTI · 1674317

Materials Data on SrCa2I6 by Materials Project

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Abstract

SrCa2I6 is Molybdenite-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Sr2+ is bonded to six I1- atoms to form SrI6 octahedra that share corners with four equivalent CaI6 pentagonal pyramids and edges with four equivalent CaI6 pentagonal pyramids. There are a spread of Sr–I bond distances ranging from 3.22–3.33 Å. Ca2+ is bonded to six I1- atoms to form distorted CaI6 pentagonal pyramids that share corners with two equivalent SrI6 octahedra, corners with two equivalent CaI6 pentagonal pyramids, edges with two equivalent SrI6 octahedra, and edges with two equivalent CaI6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 47–75°. There are a spread of Ca–I bond distances ranging from 3.17–3.29 Å. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted T-shaped geometry to one Sr2+ and two equivalent Ca2+ atoms. In the second I1- site, I1- is bonded in a 3-coordinate geometry to one Sr2+ and two equivalent Ca2+ atoms. In the third I1- site, I1- is bonded in a distorted T-shaped geometry to one Sr2+ and two equivalent Ca2+ atoms.

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36 MATERIALS SCIENCECa-I-Srcrystal structureSrCa2I6

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2020-04-29. Materials Data on SrCa2I6 by Materials Project. https://doi.org/10.17188/1674317

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