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DOE OSTI · 1665636

Materials Data on BaLuCo4O7 by Materials Project

Abstract

BaLuCo4O7 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. Ba2+ is bonded in a 12-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.81–3.31 Å. Lu3+ is bonded to six O2- atoms to form LuO6 octahedra that share corners with twelve CoO4 tetrahedra. There are a spread of Lu–O bond distances ranging from 2.19–2.26 Å. There are four inequivalent Co+2.25+ sites. In the first Co+2.25+ site, Co+2.25+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent LuO6 octahedra and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–59°. There are a spread of Co–O bond distances ranging from 1.96–2.01 Å. In the second Co+2.25+ site, Co+2.25+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent LuO6 octahedra and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–57°. There are a spread of Co–O bond distances ranging from 1.86–1.94 Å. In the third Co+2.25+ site, Co+2.25+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent LuO6 octahedra and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–58°. There are a spread of Co–O bond distances ranging from 1.95–2.00 Å. In the fourth Co+2.25+ site, Co+2.25+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three equivalent LuO6 octahedra and corners with six CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–60°. There is two shorter (1.94 Å) and two longer (2.01 Å) Co–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ba2+, one Lu3+, and two Co+2.25+ atoms to form distorted corner-sharing OBaLuCo2 trigonal pyramids. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Lu3+, and two Co+2.25+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Lu3+, and two Co+2.25+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Lu3+, and two Co+2.25+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Lu3+, and two Co+2.25+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Lu3+, and two Co+2.25+ atoms. In the seventh O2- site, O2- is bonded to four Co+2.25+ atoms to form corner-sharing OCo4 tetrahedra.

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2020-07-14. Materials Data on BaLuCo4O7 by Materials Project. https://doi.org/10.17188/1665636

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