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DOE OSTI · 1698503

Materials Data on Ba5Mn(Co2O7)2 by Materials Project

Abstract

Ba5Mn(Co2O7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with three equivalent BaO12 cuboctahedra, edges with six equivalent BaO12 cuboctahedra, edges with six CoO4 tetrahedra, a faceface with one MnO6 octahedra, and a faceface with one CoO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.84–3.37 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 2.78–3.24 Å. In the third Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with five BaO12 cuboctahedra, a cornercorner with one CoO6 octahedra, corners with two equivalent MnO6 octahedra, faces with two equivalent BaO12 cuboctahedra, a faceface with one MnO6 octahedra, faces with five CoO6 octahedra, and a faceface with one CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 10°. There are a spread of Ba–O bond distances ranging from 2.81–3.25 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.72–2.96 Å. In the fifth Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.68–2.95 Å. Mn7+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent BaO12 cuboctahedra, corners with three CoO4 tetrahedra, faces with two BaO12 cuboctahedra, and a faceface with one CoO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.91–2.03 Å. There are four inequivalent Co+2.75+ sites. In the first Co+2.75+ site, Co+2.75+ is bonded to four O2- atoms to form CoO4 tetrahedra that share a cornercorner with one CoO6 octahedra, corners with two equivalent MnO6 octahedra, and edges with three equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 14–16°. There are a spread of Co–O bond distances ranging from 1.74–1.84 Å. In the second Co+2.75+ site, Co+2.75+ is bonded to four O2- atoms to form CoO4 tetrahedra that share a cornercorner with one MnO6 octahedra, corners with two equivalent CoO6 octahedra, edges with three equivalent BaO12 cuboctahedra, and a faceface with one BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 13–16°. There are a spread of Co–O bond distances ranging from 1.74–1.85 Å. In the third Co+2.75+ site, Co+2.75+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one BaO12 cuboctahedra, corners with three CoO4 tetrahedra, faces with three BaO12 cuboctahedra, and a faceface with one CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.94–2.12 Å. In the fourth Co+2.75+ site, Co+2.75+ is bonded to six O2- atoms to form CoO6 octahedra that share faces with three equivalent BaO12 cuboctahedra, a faceface with one MnO6 octahedra, and a faceface with one CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–1.96 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+, one Mn7+, and one Co+2.75+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+ and two Co+2.75+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+, one Mn7+, and one Co+2.75+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+ and two Co+2.75+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+ and two Co+2.75+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+, one Mn7+, and one Co+2.75+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to four Ba2+ and one Co+2.75+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to four Ba2+ and one Co+2.75+ atom. In the ninth O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+ and two Co+2.75+ atoms. In the tenth O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+, one Mn7+, and one Co+2.75+ atom. In the eleventh O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+ and two Co+2.75+ atoms. In the twelfth O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+, one Mn7+, and one Co+2.75+ atom. In the thirteenth O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+, one Mn7+, and one Co+2.75+ atom. In the fourteenth O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+ and two Co+2.75+ atoms.

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2020-05-01. Materials Data on Ba5Mn(Co2O7)2 by Materials Project. https://doi.org/10.17188/1698503

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36 MATERIALS SCIENCE↗