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DOE OSTI · 1739548

Materials Data on Cr3Fe2O15 by Materials Project

Abstract

Cr2FeO8CrFeO7 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two CrFeO7 ribbons oriented in the (0, 1, 0) direction and one Cr2FeO8 sheet oriented in the (0, 0, 1) direction. In each CrFeO7 ribbon, Cr is bonded to four O atoms to form CrO4 tetrahedra that share corners with two equivalent FeO5 trigonal bipyramids. There are a spread of Cr–O bond distances ranging from 1.60–1.80 Å. Fe is bonded to five O atoms to form FeO5 trigonal bipyramids that share corners with two equivalent CrO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.65–1.90 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Fe atom. In the second O site, O is bonded in a single-bond geometry to one Fe atom. In the third O site, O is bonded in a single-bond geometry to one Fe atom. In the fourth O site, O is bonded in a single-bond geometry to one Cr atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Cr and one Fe atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to one Cr and one Fe atom. In the seventh O site, O is bonded in a single-bond geometry to one Cr atom. In the Cr2FeO8 sheet, there are two inequivalent Cr sites. In the first Cr site, Cr is bonded to four O atoms to form CrO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 24–59°. There are a spread of Cr–O bond distances ranging from 1.61–1.77 Å. In the second Cr site, Cr is bonded to four O atoms to form CrO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 11–33°. There are a spread of Cr–O bond distances ranging from 1.60–1.71 Å. Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six CrO4 tetrahedra and an edgeedge with one FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.10 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one Cr and two equivalent Fe atoms. In the second O site, O is bonded in a linear geometry to one Cr and one Fe atom. In the third O site, O is bonded in a single-bond geometry to one Cr atom. In the fourth O site, O is bonded in a single-bond geometry to one Cr atom. In the fifth O site, O is bonded in a single-bond geometry to one Cr atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to one Cr and one Fe atom. In the seventh O site, O is bonded in a bent 150 degrees geometry to one Cr and one Fe atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to one Cr and one Fe atom.

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2020-04-29. Materials Data on Cr3Fe2O15 by Materials Project. https://doi.org/10.17188/1739548

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