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DOE OSTI · 1754439

Materials Data on V2Cd3O8 by Materials Project

Abstract

Cd3V2O8 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are two inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with six equivalent CdO6 octahedra and corners with two equivalent CdO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–54°. There are a spread of V–O bond distances ranging from 1.73–1.77 Å. In the second V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with six equivalent CdO6 octahedra and corners with two equivalent CdO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–58°. There are a spread of V–O bond distances ranging from 1.69–1.84 Å. There are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with three equivalent CdO4 tetrahedra, corners with six VO4 tetrahedra, and edges with two equivalent CdO6 octahedra. There are a spread of Cd–O bond distances ranging from 2.25–2.49 Å. In the second Cd2+ site, Cd2+ is bonded to four O2- atoms to form distorted CdO4 tetrahedra that share corners with six equivalent CdO6 octahedra and corners with four VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 72–78°. There are a spread of Cd–O bond distances ranging from 2.22–2.38 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one V5+ and two equivalent Cd2+ atoms. In the second O2- site, O2- is bonded to one V5+ and three Cd2+ atoms to form a mixture of distorted edge and corner-sharing OVCd3 tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two equivalent Cd2+ atoms. In the fourth O2- site, O2- is bonded to one V5+ and three Cd2+ atoms to form a mixture of distorted edge and corner-sharing OVCd3 tetrahedra. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two Cd2+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one Cd2+ atom.

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2020-04-30. Materials Data on V2Cd3O8 by Materials Project. https://doi.org/10.17188/1754439

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36 MATERIALS SCIENCE↗