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DOE OSTI · 1322713

Materials Data on ZnCoNi2O7 by Materials Project

Abstract

CoNi2ZnO7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Co4+ sites. In the first Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three NiO4 tetrahedra, corners with two equivalent NiO5 trigonal bipyramids, an edgeedge with one CoO6 octahedra, an edgeedge with one ZnO6 octahedra, and edges with two equivalent NiO6 pentagonal pyramids. There are a spread of Co–O bond distances ranging from 1.77–1.99 Å. In the second Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent NiO6 pentagonal pyramids, corners with four NiO4 tetrahedra, an edgeedge with one CoO6 octahedra, and an edgeedge with one ZnO6 octahedra. There are a spread of Co–O bond distances ranging from 1.75–2.04 Å. There are four inequivalent Ni4+ sites. In the first Ni4+ site, Ni4+ is bonded to four O2- atoms to form NiO4 tetrahedra that share corners with three CoO6 octahedra, corners with three equivalent ZnO6 octahedra, and a cornercorner with one NiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 50–67°. There are a spread of Ni–O bond distances ranging from 1.87–2.30 Å. In the second Ni4+ site, Ni4+ is bonded to five O2- atoms to form NiO5 trigonal bipyramids that share a cornercorner with one ZnO6 octahedra, corners with two equivalent CoO6 octahedra, a cornercorner with one NiO4 tetrahedra, and an edgeedge with one NiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 39–57°. There are a spread of Ni–O bond distances ranging from 1.79–2.00 Å. In the third Ni4+ site, Ni4+ is bonded to six O2- atoms to form distorted NiO6 pentagonal pyramids that share a cornercorner with one ZnO6 octahedra, corners with two equivalent CoO6 octahedra, corners with two NiO4 tetrahedra, an edgeedge with one ZnO6 octahedra, edges with two equivalent CoO6 octahedra, and an edgeedge with one NiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 33–67°. There are a spread of Ni–O bond distances ranging from 1.86–2.19 Å. In the fourth Ni4+ site, Ni4+ is bonded to four O2- atoms to form distorted NiO4 tetrahedra that share a cornercorner with one ZnO6 octahedra, corners with four CoO6 octahedra, a cornercorner with one NiO6 pentagonal pyramid, and a cornercorner with one NiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 36–73°. There are a spread of Ni–O bond distances ranging from 1.78–1.90 Å. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Zn–O bond distances ranging from 2.05–2.61 Å. In the second Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 octahedra that share a cornercorner with one NiO6 pentagonal pyramid, corners with four NiO4 tetrahedra, a cornercorner with one NiO5 trigonal bipyramid, edges with two CoO6 octahedra, and an edgeedge with one NiO6 pentagonal pyramid. There are a spread of Zn–O bond distances ranging from 1.98–2.33 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ni4+, one Zn2+, and one O2- atom. The O–O bond length is 1.33 Å. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Co4+, one Ni4+, and two Zn2+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Co4+, one Ni4+, and one Zn2+ atom. In the fourth O2- site, O2- is bonded in a distorted tetrahedral geometry to one Co4+, two Ni4+, and one Zn2+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Co4+, one Ni4+, and one Zn2+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Co4+, one Ni4+, and one Zn2+ atom. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to one Co4+, one Ni4+, and one Zn2+ atom. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to one Ni4+ and two Zn2+ atoms. In the ninth O2- site, O2- is bonded in a distorted water-like geometry to two Ni4+ and one Zn2+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two Ni4+ and one O2- atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Co4+ and one Ni4+ atom. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Co4+, two Ni4+, and one Zn2+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Co4+, one Ni4+, and one Zn2+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Co4+ and two Ni4+ atoms.

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2020-04-30. Materials Data on ZnCoNi2O7 by Materials Project. https://doi.org/10.17188/1322713

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36 MATERIALS SCIENCE↗