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DOE OSTI · 1749075

Materials Data on Ba2CaY(Co4O7)2 by Materials Project

Abstract

Ba2CaY(Co4O7)2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Ba–O bond distances ranging from 2.91–3.47 Å. In the second Ba2+ site, Ba2+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Ba–O bond distances ranging from 2.88–3.50 Å. Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with twelve CoO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.31–2.35 Å. Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with twelve CoO4 tetrahedra. There are a spread of Y–O bond distances ranging from 2.22–2.38 Å. There are six inequivalent Co+2.38+ sites. In the first Co+2.38+ site, Co+2.38+ is bonded to four O2- atoms to form CoO4 tetrahedra that share a cornercorner with one YO6 octahedra, corners with two equivalent CaO6 octahedra, and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–56°. There are a spread of Co–O bond distances ranging from 1.87–1.94 Å. In the second Co+2.38+ site, Co+2.38+ is bonded to four O2- atoms to form CoO4 tetrahedra that share a cornercorner with one YO6 octahedra, corners with two equivalent CaO6 octahedra, and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–59°. There are a spread of Co–O bond distances ranging from 1.92–2.03 Å. In the third Co+2.38+ site, Co+2.38+ is bonded to four O2- atoms to form CoO4 tetrahedra that share a cornercorner with one CaO6 octahedra, corners with two equivalent YO6 octahedra, and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–58°. There are a spread of Co–O bond distances ranging from 1.95–2.01 Å. In the fourth Co+2.38+ site, Co+2.38+ is bonded to four O2- atoms to form CoO4 tetrahedra that share a cornercorner with one CaO6 octahedra, corners with two equivalent YO6 octahedra, and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–59°. There are a spread of Co–O bond distances ranging from 1.95–2.01 Å. In the fifth Co+2.38+ site, Co+2.38+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent YO6 octahedra and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–56°. There is two shorter (1.86 Å) and two longer (1.94 Å) Co–O bond length. In the sixth Co+2.38+ site, Co+2.38+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent CaO6 octahedra and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–52°. There are a spread of Co–O bond distances ranging from 1.84–2.02 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+, one Y3+, and two Co+2.38+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Y3+, and two Co+2.38+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+, one Ca2+, and two Co+2.38+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Ca2+, and two Co+2.38+ atoms. In the fifth O2- site, O2- is bonded in a tetrahedral geometry to four Co+2.38+ atoms. In the sixth O2- site, O2- is bonded in a tetrahedral geometry to four Co+2.38+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Ba2+, one Ca2+, and two equivalent Co+2.38+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Ba2+, one Ca2+, and two Co+2.38+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two Ba2+, one Y3+, and two equivalent Co+2.38+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two Ba2+, one Y3+, and two Co+2.38+ atoms.

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2020-05-03. Materials Data on Ba2CaY(Co4O7)2 by Materials Project. https://doi.org/10.17188/1749075

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