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DOE OSTI · 1317883

Materials Data on CaCo2(CuO4)2 by Materials Project

Abstract

CaCo2(CuO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.45 Å. There are two inequivalent Co4+ sites. In the first Co4+ site, Co4+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with two equivalent CuO5 trigonal bipyramids. There are a spread of Co–O bond distances ranging from 1.69–1.79 Å. In the second Co4+ site, Co4+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent CuO5 trigonal bipyramids. There are a spread of Co–O bond distances ranging from 1.78–1.86 Å. There are two inequivalent Cu3+ sites. In the first Cu3+ site, Cu3+ is bonded to five O2- atoms to form CuO5 trigonal bipyramids that share corners with five CoO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.92–2.10 Å. In the second Cu3+ site, Cu3+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.88–1.91 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Co4+, and one Cu3+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Co4+, and one Cu3+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Co4+, and one Cu3+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Co4+ and one Cu3+ atom. In the fifth O2- site, O2- is bonded to two equivalent Ca2+, one Co4+, and one Cu3+ atom to form distorted edge-sharing OCa2CoCu tetrahedra. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Co4+, and one Cu3+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co4+ and one Cu3+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Co4+ and two Cu3+ atoms.

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2020-08-03. Materials Data on CaCo2(CuO4)2 by Materials Project. https://doi.org/10.17188/1317883

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