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DOE OSTI · 1747228

Materials Data on Cr4Fe2O19 by Materials Project

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Abstract

Cr4Fe2O19 crystallizes in the monoclinic P2/c space group. The structure is two-dimensional and consists of one Cr4Fe2O19 sheet oriented in the (0, 1, 0) direction. 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 FeO6 octahedra. The corner-sharing octahedra tilt angles range from 33–43°. There are a spread of Cr–O bond distances ranging from 1.60–1.76 Å. In the second Cr site, Cr is bonded to four O atoms to form CrO4 tetrahedra that share a cornercorner with one FeO6 octahedra and a cornercorner with one CrO4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. There are a spread of Cr–O bond distances ranging from 1.60–1.78 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four equivalent CrO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.83–2.10 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four CrO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.96–2.10 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a linear geometry to one Cr and one Fe atom. In the second O site, O is bonded in a single-bond geometry to one Cr 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 bent 150 degrees geometry to one Cr and one Fe atom. In the fifth O site, O is bonded in a single-bond geometry to 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 eighth O site, O is bonded in a bent 150 degrees geometry to one Cr and one Fe atom. In the ninth O site, O is bonded in a bent 120 degrees geometry to two equivalent Cr atoms. In the tenth O site, O is bonded in a single-bond geometry to one Cr atom.

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36 MATERIALS SCIENCECr-Fe-OCr4Fe2O19crystal structure

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2020-05-02. Materials Data on Cr4Fe2O19 by Materials Project. https://doi.org/10.17188/1747228

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