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DOE OSTI · 1715702

Materials Data on KCaI3 by Materials Project

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Abstract

KCaI3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight I1- atoms. There are a spread of K–I bond distances ranging from 3.59–4.04 Å. Ca2+ is bonded to six I1- atoms to form a mixture of edge and corner-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are two shorter (3.16 Å) and four longer (3.18 Å) Ca–I bond lengths. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 5-coordinate geometry to three equivalent K1+ and two equivalent Ca2+ atoms. In the second I1- site, I1- is bonded to two equivalent K1+ and two equivalent Ca2+ atoms to form distorted corner-sharing IK2Ca2 tetrahedra.

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36 MATERIALS SCIENCECa-I-Kcrystal structureKCaI3

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2020-05-03. Materials Data on KCaI3 by Materials Project. https://doi.org/10.17188/1715702

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