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DOE OSTI · 1318547

Materials Data on Ti4ZnO8 by Materials Project

Abstract

Ti4ZnO8 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Ti+3.50+ sites. In the first Ti+3.50+ site, Ti+3.50+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.87–2.40 Å. In the second Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with two equivalent ZnO5 square pyramids, edges with four TiO6 octahedra, and a faceface with one ZnO5 square pyramid. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ti–O bond distances ranging from 1.92–2.23 Å. In the third Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with two equivalent ZnO5 square pyramids, and edges with four TiO6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Ti–O bond distances ranging from 1.94–2.10 Å. In the fourth Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four TiO6 octahedra, corners with two equivalent ZnO5 square pyramids, edges with two equivalent TiO6 octahedra, and an edgeedge with one ZnO5 square pyramid. The corner-sharing octahedra tilt angles range from 49–52°. There are a spread of Ti–O bond distances ranging from 1.98–2.13 Å. Zn2+ is bonded to five O2- atoms to form ZnO5 square pyramids that share corners with six TiO6 octahedra, an edgeedge with one TiO6 octahedra, edges with two equivalent ZnO5 square pyramids, and a faceface with one TiO6 octahedra. The corner-sharing octahedra tilt angles range from 3–54°. There are a spread of Zn–O bond distances ranging from 2.08–2.17 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti+3.50+ atoms. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti+3.50+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti+3.50+ atoms. In the fourth O2- site, O2- is bonded to three Ti+3.50+ and one Zn2+ atom to form distorted OTi3Zn trigonal pyramids that share corners with two equivalent OTi3Zn trigonal pyramids, edges with two equivalent OTi3Zn2 square pyramids, and edges with two equivalent OTi3Zn2 trigonal bipyramids. In the fifth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Ti+3.50+ atoms. In the sixth O2- site, O2- is bonded to three Ti+3.50+ and two equivalent Zn2+ atoms to form distorted OTi3Zn2 trigonal bipyramids that share corners with two equivalent OTi3Zn2 square pyramids, an edgeedge with one OTi3Zn2 square pyramid, edges with two equivalent OTi3Zn2 trigonal bipyramids, and edges with two equivalent OTi3Zn trigonal pyramids. In the seventh O2- site, O2- is bonded to three Ti+3.50+ and two equivalent Zn2+ atoms to form OTi3Zn2 square pyramids that share corners with two equivalent OTi3Zn2 trigonal bipyramids, edges with two equivalent OTi3Zn2 square pyramids, an edgeedge with one OTi3Zn2 trigonal bipyramid, and edges with two equivalent OTi3Zn trigonal pyramids. In the eighth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Ti+3.50+ atoms.

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2020-07-22. Materials Data on Ti4ZnO8 by Materials Project. https://doi.org/10.17188/1318547

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