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DOE OSTI · 1339667

Materials Data on CaFe2F10 by Materials Project

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Abstract

CaFe2F10 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. Ca is bonded to seven F atoms to form distorted CaF7 pentagonal bipyramids that share corners with four FeF6 octahedra and edges with two equivalent FeF6 octahedra. The corner-sharing octahedra tilt angles range from 15–40°. There are a spread of Ca–F bond distances ranging from 2.25–2.48 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six F atoms to form FeF6 octahedra that share corners with two equivalent FeF6 octahedra, a cornercorner with one CaF7 pentagonal bipyramid, and edges with two equivalent CaF7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 31°. There are a spread of Fe–F bond distances ranging from 1.76–2.02 Å. In the second Fe site, Fe is bonded to six F atoms to form FeF6 octahedra that share corners with two equivalent FeF6 octahedra and corners with three equivalent CaF7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 24°. There are a spread of Fe–F bond distances ranging from 1.76–2.00 Å. There are ten inequivalent F sites. In the first F site, F is bonded in a distorted bent 120 degrees geometry to one Ca and one Fe atom. In the second F site, F is bonded in a bent 150 degrees geometry to one Ca and one Fe atom. In the third F site, F is bonded in a distorted bent 120 degrees geometry to one Ca and one Fe atom. In the fourth F site, F is bonded in a bent 150 degrees geometry to one Ca and one Fe atom. In the fifth F site, F is bonded in a bent 150 degrees geometry to one Ca and one Fe atom. In the sixth F site, F is bonded in a single-bond geometry to one Fe atom. In the seventh F site, F is bonded in a single-bond geometry to one Fe atom. In the eighth F site, F is bonded in a linear geometry to one Ca and one Fe atom. In the ninth F site, F is bonded in a 3-coordinate geometry to one Ca and two equivalent Fe atoms. In the tenth F site, F is bonded in a bent 150 degrees geometry to two equivalent Fe atoms.

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36 MATERIALS SCIENCECa-F-FeCaFe2F10crystal structure

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2020-04-30. Materials Data on CaFe2F10 by Materials Project. https://doi.org/10.17188/1339667

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