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DOE OSTI · 1305686

Materials Data on Ti4O7 by Materials Project

Abstract

Ti4O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are eight inequivalent Ti+3.50+ sites. In the first Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent TiO6 octahedra, corners with three equivalent TiO5 trigonal bipyramids, and edges with two TiO6 octahedra. The corner-sharing octahedra tilt angles range from 46–56°. There are a spread of Ti–O bond distances ranging from 1.97–2.10 Å. In the second Ti+3.50+ site, Ti+3.50+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ti–O bond distances ranging from 1.85–2.19 Å. In the third Ti+3.50+ site, Ti+3.50+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share corners with three TiO6 octahedra, an edgeedge with one TiO6 octahedra, and an edgeedge with one TiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 38–55°. There are a spread of Ti–O bond distances ranging from 1.86–2.13 Å. In the fourth Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with six TiO6 octahedra and edges with two TiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 43–56°. There are a spread of Ti–O bond distances ranging from 1.91–2.16 Å. In the fifth Ti+3.50+ site, Ti+3.50+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share corners with five TiO6 octahedra, an edgeedge with one TiO6 octahedra, and an edgeedge with one TiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 27–69°. There are a spread of Ti–O bond distances ranging from 1.85–2.06 Å. In the sixth Ti+3.50+ site, Ti+3.50+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ti–O bond distances ranging from 1.91–2.54 Å. In the seventh Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with two equivalent TiO5 trigonal bipyramids, and edges with two TiO6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of Ti–O bond distances ranging from 1.90–2.09 Å. In the eighth 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 three TiO5 trigonal bipyramids, and edges with two TiO6 octahedra. The corner-sharing octahedra tilt angles range from 43–55°. There are a spread of Ti–O bond distances ranging from 1.93–2.21 Å. There are fourteen 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 trigonal non-coplanar geometry to three Ti+3.50+ atoms. In the third O2- site, O2- is bonded in a T-shaped geometry to three Ti+3.50+ atoms. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti+3.50+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti+3.50+ atoms. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to five Ti+3.50+ atoms. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to four Ti+3.50+ atoms. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti+3.50+ atoms. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti+3.50+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to four Ti+3.50+ atoms. In the eleventh O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti+3.50+ atoms. In the twelfth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti+3.50+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ti+3.50+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Ti+3.50+ atoms.

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2020-05-01. Materials Data on Ti4O7 by Materials Project. https://doi.org/10.17188/1305686

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