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DOE OSTI · 1758710

Materials Data on BaHoFe4O7 by Materials Project

Abstract

BaHoFe4O7 is Hausmannite-derived structured and crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.78–3.37 Å. Ho3+ is bonded to six O2- atoms to form HoO6 octahedra that share corners with twelve FeO4 tetrahedra. There are a spread of Ho–O bond distances ranging from 2.23–2.35 Å. There are four inequivalent Fe+2.25+ sites. In the first Fe+2.25+ site, Fe+2.25+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three equivalent HoO6 octahedra and corners with six FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–59°. There are a spread of Fe–O bond distances ranging from 1.92–1.94 Å. In the second Fe+2.25+ site, Fe+2.25+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three equivalent HoO6 octahedra and corners with six FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–67°. There are a spread of Fe–O bond distances ranging from 1.99–2.06 Å. In the third Fe+2.25+ site, Fe+2.25+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three equivalent HoO6 octahedra and corners with six FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–67°. There are a spread of Fe–O bond distances ranging from 1.98–2.08 Å. In the fourth Fe+2.25+ site, Fe+2.25+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three equivalent HoO6 octahedra and corners with six FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–63°. There are a spread of Fe–O bond distances ranging from 1.97–2.14 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Ho3+, and two Fe+2.25+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Ho3+, and two Fe+2.25+ atoms. In the third O2- site, O2- is bonded to one Ba2+, one Ho3+, and two Fe+2.25+ atoms to form distorted corner-sharing OBaHoFe2 tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Ho3+, and two Fe+2.25+ atoms. In the fifth O2- site, O2- is bonded to one Ba2+, one Ho3+, and two Fe+2.25+ atoms to form distorted corner-sharing OBaHoFe2 tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Ho3+, and two Fe+2.25+ atoms. In the seventh O2- site, O2- is bonded to four Fe+2.25+ atoms to form corner-sharing OFe4 tetrahedra.

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2020-09-03. Materials Data on BaHoFe4O7 by Materials Project. https://doi.org/10.17188/1758710

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