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DOE OSTI · 1318516

Materials Data on CaV4(CoO7)2 by Materials Project

Abstract

CaV4(CoO7)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.60 Å. There are four inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with three CoO6 octahedra. The corner-sharing octahedra tilt angles range from 44–60°. There are a spread of V–O bond distances ranging from 1.68–1.79 Å. In the second V5+ site, V5+ is bonded to five O2- atoms to form distorted VO5 trigonal bipyramids that share corners with two equivalent CoO6 octahedra and a cornercorner with one VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–40°. There are a spread of V–O bond distances ranging from 1.65–2.02 Å. In the third V5+ site, V5+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of V–O bond distances ranging from 1.71–2.30 Å. In the fourth V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with four CoO6 octahedra and a cornercorner with one VO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 43–58°. There are a spread of V–O bond distances ranging from 1.69–1.80 Å. There are two inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three VO4 tetrahedra, corners with two equivalent VO5 trigonal bipyramids, and an edgeedge with one CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.87–2.17 Å. In the second Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with four VO4 tetrahedra and an edgeedge with one CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–2.05 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ca2+ and one V5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ca2+, one V5+, and one Co3+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+ and one Co3+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one V5+, and one Co3+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+ and one Co3+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two Co3+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one Co3+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ca2+ and one V5+ atom. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to two V5+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two V5+ atoms. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one V5+ and two Co3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Ca2+, two V5+, and one Co3+ atom. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+, one V5+, and one Co3+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to two V5+ and one Co3+ atom.

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2020-05-30. Materials Data on CaV4(CoO7)2 by Materials Project. https://doi.org/10.17188/1318516

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36 MATERIALS SCIENCE↗