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DOE OSTI · 1742361

Materials Data on Ba4Y2Fe2O11 by Materials Project

Abstract

Ba4Y2Fe2O11 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of Ba–O bond distances ranging from 2.73–3.20 Å. In the second Ba site, Ba is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of Ba–O bond distances ranging from 2.75–3.19 Å. There are two inequivalent Y sites. In the first Y site, Y is bonded to six O atoms to form YO6 octahedra that share corners with two equivalent YO6 octahedra, corners with two equivalent FeO5 square pyramids, and corners with two equivalent FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 14°. There are a spread of Y–O bond distances ranging from 2.19–2.34 Å. In the second Y site, Y is bonded to six O atoms to form YO6 octahedra that share corners with two equivalent YO6 octahedra, corners with two equivalent FeO5 square pyramids, and corners with two equivalent FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 15°. There are a spread of Y–O bond distances ranging from 2.19–2.42 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to five O atoms to form distorted FeO5 square pyramids that share corners with four YO6 octahedra. The corner-sharing octahedra tilt angles range from 4–10°. There are a spread of Fe–O bond distances ranging from 1.88–2.02 Å. In the second Fe site, Fe is bonded to four O atoms to form distorted FeO4 tetrahedra that share corners with four YO6 octahedra. The corner-sharing octahedra tilt angles range from 4–37°. There is two shorter (1.83 Å) and two longer (1.84 Å) Fe–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to four Ba, one Y, and one Fe atom. In the second O site, O is bonded in a 4-coordinate geometry to four equivalent Ba and two equivalent Y atoms. In the third O site, O is bonded in a distorted single-bond geometry to four equivalent Ba and one Fe atom. In the fourth O site, O is bonded in a 6-coordinate geometry to four equivalent Ba and two equivalent Y atoms. In the fifth O site, O is bonded in a distorted linear geometry to four Ba, one Y, and one Fe atom. In the sixth O site, O is bonded in a 2-coordinate geometry to three equivalent Ba, one Y, and one Fe atom. In the seventh O site, O is bonded in a distorted linear geometry to four Ba, one Y, and one Fe atom. In the eighth O site, O is bonded in a 4-coordinate geometry to two equivalent Ba, one Y, and one Fe atom. In the ninth O site, O is bonded in a distorted octahedral geometry to four Ba, one Y, and one Fe atom.

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2020-05-03. Materials Data on Ba4Y2Fe2O11 by Materials Project. https://doi.org/10.17188/1742361

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