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DOE OSTI · 1737235

Materials Data on Ba2V2FeO9 by Materials Project

Abstract

Ba2V2FeO9 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 11-coordinate geometry to eleven O atoms. There are a spread of Ba–O bond distances ranging from 2.71–3.20 Å. In the second Ba site, Ba is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ba–O bond distances ranging from 2.73–3.24 Å. There are two inequivalent V sites. In the first V site, V is bonded to four O atoms to form VO4 tetrahedra that share corners with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 56°. There is two shorter (1.70 Å) and two longer (1.79 Å) V–O bond length. In the second V site, V is bonded to four O atoms to form VO4 tetrahedra that share corners with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of V–O bond distances ranging from 1.69–1.85 Å. Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four VO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.88–2.11 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Ba and one V atom. In the second O site, O is bonded in a 2-coordinate geometry to two Ba, one V, and one Fe atom. In the third O site, O is bonded in a distorted single-bond geometry to four Ba and one V atom. In the fourth O site, O is bonded in a distorted single-bond geometry to two Ba and one V atom. In the fifth O site, O is bonded in a distorted single-bond geometry to three Ba and one V atom. In the sixth O site, O is bonded in a 3-coordinate geometry to one Ba, one V, and two equivalent Fe atoms. In the seventh O site, O is bonded in a water-like geometry to one Ba and two equivalent Fe atoms.

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2020-05-02. Materials Data on Ba2V2FeO9 by Materials Project. https://doi.org/10.17188/1737235

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36 MATERIALS SCIENCE↗