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DOE OSTI · 1308588

Materials Data on Fe3OF5 by Materials Project

Abstract

Fe3OF5 is zeta iron carbide-derived structured and crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are four inequivalent Fe+2.33+ sites. In the first Fe+2.33+ site, Fe+2.33+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with eight equivalent FeO2F4 octahedra and edges with two equivalent FeF6 octahedra. The corner-sharing octahedra tilt angles range from 46–49°. There are two shorter (2.07 Å) and four longer (2.14 Å) Fe–F bond lengths. In the second Fe+2.33+ site, Fe+2.33+ is bonded to one O2- and five F1- atoms to form FeOF5 octahedra that share corners with eight FeO2F4 octahedra and edges with two equivalent FeOF5 octahedra. The corner-sharing octahedra tilt angles range from 47–56°. The Fe–O bond length is 2.04 Å. There are a spread of Fe–F bond distances ranging from 2.05–2.18 Å. In the third Fe+2.33+ site, Fe+2.33+ is bonded to two equivalent O2- and four F1- atoms to form FeO2F4 octahedra that share corners with eight FeF6 octahedra and edges with two equivalent FeO2F4 octahedra. The corner-sharing octahedra tilt angles range from 46–56°. Both Fe–O bond lengths are 1.92 Å. There are a spread of Fe–F bond distances ranging from 1.99–2.21 Å. In the fourth Fe+2.33+ site, Fe+2.33+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with eight equivalent FeOF5 octahedra and edges with two equivalent FeF6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are two shorter (2.04 Å) and four longer (2.13 Å) Fe–F bond lengths. O2- is bonded in a trigonal planar geometry to three Fe+2.33+ atoms. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to three Fe+2.33+ atoms. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to three Fe+2.33+ atoms. In the third F1- site, F1- is bonded in a distorted trigonal planar geometry to three Fe+2.33+ atoms. In the fourth F1- site, F1- is bonded in a 3-coordinate geometry to three Fe+2.33+ atoms. In the fifth F1- site, F1- is bonded in a distorted trigonal planar geometry to three Fe+2.33+ atoms.

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2020-08-03. Materials Data on Fe3OF5 by Materials Project. https://doi.org/10.17188/1308588

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