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DOE OSTI · 1320776

Materials Data on Mg2Co2O5 by Materials Project

Abstract

Mg2Co2O5 is Aluminum carbonitride-like structured and crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mg–O bond distances ranging from 2.06–2.36 Å. In the second Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mg–O bond distances ranging from 2.06–2.36 Å. There are two inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to five O2- atoms to form corner-sharing CoO5 trigonal bipyramids. There are a spread of Co–O bond distances ranging from 1.84–2.05 Å. In the second Co3+ site, Co3+ is bonded to five O2- atoms to form corner-sharing CoO5 trigonal bipyramids. There are a spread of Co–O bond distances ranging from 1.84–2.05 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four Mg2+ and two Co3+ atoms to form OMg4Co2 octahedra that share corners with twelve OMg2Co2 tetrahedra, edges with two equivalent OMg4Co2 octahedra, and edges with six OMg2Co2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Mg2+ and two Co3+ atoms to form OMg2Co2 tetrahedra that share corners with four equivalent OMg4Co2 octahedra, corners with eight OMg2Co2 tetrahedra, an edgeedge with one OMg4Co2 octahedra, and edges with two equivalent OMg2Co2 tetrahedra. The corner-sharing octahedra tilt angles range from 14–64°. In the third O2- site, O2- is bonded to two equivalent Mg2+ and two Co3+ atoms to form OMg2Co2 tetrahedra that share corners with four equivalent OMg4Co2 octahedra, corners with eight OMg2Co2 tetrahedra, an edgeedge with one OMg4Co2 octahedra, and edges with two equivalent OMg2Co2 tetrahedra. The corner-sharing octahedra tilt angles range from 15–64°. In the fourth O2- site, O2- is bonded to two Mg2+ and two equivalent Co3+ atoms to form distorted OMg2Co2 tetrahedra that share corners with two equivalent OMg4Co2 octahedra, corners with six OMg2Co2 tetrahedra, edges with two equivalent OMg4Co2 octahedra, and edges with three OMg2Co2 tetrahedra. The corner-sharing octahedral tilt angles are 60°. In the fifth O2- site, O2- is bonded to two Mg2+ and two equivalent Co3+ atoms to form distorted OMg2Co2 tetrahedra that share corners with two equivalent OMg4Co2 octahedra, corners with six OMg2Co2 tetrahedra, edges with two equivalent OMg4Co2 octahedra, and edges with three OMg2Co2 tetrahedra. The corner-sharing octahedral tilt angles are 60°.

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2020-05-02. Materials Data on Mg2Co2O5 by Materials Project. https://doi.org/10.17188/1320776

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