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DOE OSTI · 1322729

Materials Data on ZnCo3O7 by Materials Project

Abstract

Co3ZnO7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are six inequivalent Co4+ sites. In the first Co4+ site, Co4+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three CoO6 octahedra and corners with three equivalent ZnO5 square pyramids. The corner-sharing octahedra tilt angles range from 42–64°. There are a spread of Co–O bond distances ranging from 1.72–1.83 Å. In the second Co4+ site, Co4+ is bonded to five O2- atoms to form CoO5 trigonal bipyramids that share corners with two equivalent CoO6 octahedra, a cornercorner with one ZnO5 square pyramid, and a cornercorner with one CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–57°. There are a spread of Co–O bond distances ranging from 1.74–1.95 Å. In the third Co4+ site, Co4+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Co–O bond distances ranging from 1.82–2.41 Å. In the fourth Co4+ site, Co4+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with four CoO6 octahedra and a cornercorner with one CoO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 46–58°. There are a spread of Co–O bond distances ranging from 1.72–1.84 Å. In the fifth Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one ZnO5 square pyramid, corners with three CoO4 tetrahedra, corners with two equivalent CoO5 trigonal bipyramids, and an edgeedge with one CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.86–2.16 Å. In the sixth Co4+ site, Co4+ is bonded to six O2- atoms to form distorted CoO6 octahedra that share corners with four CoO4 tetrahedra, an edgeedge with one CoO6 octahedra, and an edgeedge with one ZnO5 square pyramid. There are a spread of Co–O bond distances ranging from 1.82–2.37 Å. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Zn–O bond distances ranging from 2.03–2.12 Å. In the second Zn2+ site, Zn2+ is bonded to five O2- atoms to form distorted ZnO5 square pyramids that share a cornercorner with one CoO6 octahedra, corners with three equivalent CoO4 tetrahedra, a cornercorner with one CoO5 trigonal bipyramid, and an edgeedge with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Zn–O bond distances ranging from 1.99–2.15 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Co4+ and one Zn2+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Co4+ and one Zn2+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Co4+ and one Zn2+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Co4+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Co4+ and one Zn2+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Co4+ atoms. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to two Co4+ and one Zn2+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Co4+ and two Zn2+ atoms. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to two Co4+ atoms. In the tenth O2- site, O2- is bonded in a distorted L-shaped geometry to two Co4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to three Co4+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Co4+ and one Zn2+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Co4+ and one Zn2+ atom. In the fourteenth O2- site, O2- is bonded in a distorted T-shaped geometry to three Co4+ atoms.

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2020-04-30. Materials Data on ZnCo3O7 by Materials Project. https://doi.org/10.17188/1322729

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