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DOE OSTI · 1724736

Materials Data on Ba7Fe7F34 by Materials Project

Abstract

Ba7Fe7F34 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Ba–F bond distances ranging from 2.62–3.16 Å. In the second Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to ten F1- atoms. There are a spread of Ba–F bond distances ranging from 2.69–2.95 Å. In the third Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Ba–F bond distances ranging from 2.71–3.19 Å. There are three inequivalent Fe+2.86+ sites. In the first Fe+2.86+ site, Fe+2.86+ is bonded to six F1- atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are a spread of Fe–F bond distances ranging from 1.92–2.00 Å. In the second Fe+2.86+ site, Fe+2.86+ is bonded to six F1- atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Fe–F bond distances ranging from 1.93–1.98 Å. In the third Fe+2.86+ site, Fe+2.86+ is bonded to six F1- atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are two shorter (2.05 Å) and four longer (2.18 Å) Fe–F bond lengths. There are ten inequivalent F1- sites. In the first F1- site, F1- is bonded in a 1-coordinate geometry to three Ba2+ and one Fe+2.86+ atom. In the second F1- site, F1- is bonded in a distorted linear geometry to one Ba2+ and one Fe+2.86+ atom. In the third F1- site, F1- is bonded in a 1-coordinate geometry to three Ba2+ and one Fe+2.86+ atom. In the fourth F1- site, F1- is bonded in a bent 150 degrees geometry to two Fe+2.86+ atoms. In the fifth F1- site, F1- is bonded in a distorted single-bond geometry to three Ba2+ and one Fe+2.86+ atom. In the sixth F1- site, F1- is bonded in a 3-coordinate geometry to two Ba2+ and one Fe+2.86+ atom. In the seventh F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and two Fe+2.86+ atoms. In the eighth F1- site, F1- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+ and one Fe+2.86+ atom. In the ninth F1- site, F1- is bonded in a distorted single-bond geometry to two Ba2+ and one Fe+2.86+ atom. In the tenth F1- site, F1- is bonded in a 1-coordinate geometry to two Ba2+ and one Fe+2.86+ atom.

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2020-04-29. Materials Data on Ba7Fe7F34 by Materials Project. https://doi.org/10.17188/1724736

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36 MATERIALS SCIENCE↗