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DOE OSTI · 1654271

Materials Data on MgV3O8 by Materials Project

Abstract

MgV3O8 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO6 octahedra, corners with five VO4 tetrahedra, and edges with two equivalent VO6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are a spread of Mg–O bond distances ranging from 2.00–2.23 Å. There are three inequivalent V+4.67+ sites. In the first V+4.67+ site, V+4.67+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent VO6 octahedra, and a cornercorner with one VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 26–54°. There are a spread of V–O bond distances ranging from 1.66–1.83 Å. In the second V+4.67+ site, V+4.67+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with three equivalent MgO6 octahedra, corners with three equivalent VO6 octahedra, and a cornercorner with one VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–69°. There are a spread of V–O bond distances ranging from 1.73–1.78 Å. In the third V+4.67+ site, V+4.67+ is bonded to six O2- atoms to form VO6 octahedra that share a cornercorner with one VO6 octahedra, corners with five VO4 tetrahedra, and edges with two equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are a spread of V–O bond distances ranging from 1.85–2.17 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Mg2+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent V+4.67+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two V+4.67+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two V+4.67+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two V+4.67+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two V+4.67+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two V+4.67+ atoms. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mg2+ and one V+4.67+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two V+4.67+ atoms.

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2020-06-04. Materials Data on MgV3O8 by Materials Project. https://doi.org/10.17188/1654271

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