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DOE OSTI · 1705925

Materials Data on K2FeI4 by Materials Project

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Abstract

K2FeI4 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six I1- atoms. There are a spread of K–I bond distances ranging from 3.53–3.73 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six I1- atoms. There are a spread of K–I bond distances ranging from 3.57–3.74 Å. Fe2+ is bonded in a tetrahedral geometry to four I1- atoms. There are a spread of Fe–I bond distances ranging from 2.62–2.64 Å. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted T-shaped geometry to two K1+ and one Fe2+ atom. In the second I1- site, I1- is bonded to four K1+ and one Fe2+ atom to form a mixture of distorted corner, edge, and face-sharing IK4Fe square pyramids. In the third I1- site, I1- is bonded in a distorted T-shaped geometry to two K1+ and one Fe2+ atom.

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36 MATERIALS SCIENCEcrystal structureFe-I-KK2FeI4

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2020-05-01. Materials Data on K2FeI4 by Materials Project. https://doi.org/10.17188/1705925

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