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DOE OSTI · 1705760

Materials Data on Ba2Ho2Co4O11 by Materials Project

Abstract

Ba2Ho2Co4O11 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, faces with four CoO6 octahedra, and faces with four CoO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.72–3.08 Å. Ho3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ho–O bond distances ranging from 2.46–2.67 Å. There are four inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with four equivalent CoO6 octahedra, corners with two equivalent CoO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Co–O bond distances ranging from 1.83–2.13 Å. In the second Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with four equivalent CoO6 octahedra, corners with two equivalent CoO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Co–O bond distances ranging from 1.93–2.14 Å. In the third Co3+ site, Co3+ is bonded to five O2- atoms to form CoO5 square pyramids that share corners with two equivalent CoO6 octahedra, corners with three equivalent CoO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 11°. There are a spread of Co–O bond distances ranging from 1.83–2.36 Å. In the fourth Co3+ site, Co3+ is bonded to five O2- atoms to form CoO5 square pyramids that share corners with two equivalent CoO6 octahedra, corners with three equivalent CoO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 21°. There are a spread of Co–O bond distances ranging from 1.85–2.04 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Ba2+ and two Co3+ atoms to form a mixture of distorted edge and corner-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 6°. In the second O2- site, O2- is bonded to four equivalent Ba2+ and two Co3+ atoms to form a mixture of distorted edge and corner-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 6°. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ho3+ and two Co3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two Co3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two Co3+ atoms. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two Co3+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two Co3+ atoms.

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2020-05-03. Materials Data on Ba2Ho2Co4O11 by Materials Project. https://doi.org/10.17188/1705760

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36 MATERIALS SCIENCE↗