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DOE OSTI · 1289576

Materials Data on Ti3N2O3 by Materials Project

Abstract

Ti3N2O3 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to two N3- and four O2- atoms to form distorted TiN2O4 octahedra that share corners with four TiN2O4 octahedra, edges with five TiN3O3 octahedra, and an edgeedge with one TiN2O4 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 22–50°. There are one shorter (1.98 Å) and one longer (2.08 Å) Ti–N bond lengths. There are a spread of Ti–O bond distances ranging from 1.96–2.11 Å. In the second Ti4+ site, Ti4+ is bonded to four N3- and two O2- atoms to form distorted TiN4O2 octahedra that share corners with four TiN2O4 octahedra, edges with five TiN3O3 octahedra, and an edgeedge with one TiN2O4 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 22–50°. There are a spread of Ti–N bond distances ranging from 1.98–2.14 Å. There is one shorter (1.97 Å) and one longer (2.02 Å) Ti–O bond length. In the third Ti4+ site, Ti4+ is bonded to two N3- and four O2- atoms to form distorted TiN2O4 pentagonal pyramids that share corners with two TiN3O3 octahedra, corners with two equivalent TiN2O4 pentagonal pyramids, and edges with six TiN2O4 octahedra. The corner-sharing octahedra tilt angles range from 20–22°. There are one shorter (2.01 Å) and one longer (2.04 Å) Ti–N bond lengths. There are a spread of Ti–O bond distances ranging from 1.98–2.01 Å. In the fourth Ti4+ site, Ti4+ is bonded to three N3- and three O2- atoms to form a mixture of distorted edge and corner-sharing TiN3O3 octahedra. The corner-sharing octahedra tilt angles range from 22–36°. There are one shorter (1.98 Å) and two longer (2.03 Å) Ti–N bond lengths. There are a spread of Ti–O bond distances ranging from 1.94–2.15 Å. In the fifth Ti4+ site, Ti4+ is bonded to three N3- and three O2- atoms to form distorted TiN3O3 octahedra that share corners with three TiN3O3 octahedra, a cornercorner with one TiN2O4 pentagonal pyramid, edges with four TiN4O2 octahedra, and edges with two equivalent TiN2O4 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 30–58°. There are two shorter (2.00 Å) and one longer (2.06 Å) Ti–N bond lengths. There are a spread of Ti–O bond distances ranging from 1.93–2.19 Å. In the sixth Ti4+ site, Ti4+ is bonded to two equivalent N3- and four O2- atoms to form distorted TiN2O4 octahedra that share corners with three TiN3O3 octahedra, a cornercorner with one TiN2O4 pentagonal pyramid, edges with four TiN2O4 octahedra, and edges with two equivalent TiN2O4 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 34–58°. Both Ti–N bond lengths are 2.02 Å. There are a spread of Ti–O bond distances ranging from 1.84–2.20 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded to four Ti4+ atoms to form distorted NTi4 tetrahedra that share corners with two equivalent NTi4 tetrahedra, corners with two NTi4 trigonal pyramids, and edges with two equivalent OTi4 trigonal pyramids. In the second N3- site, N3- is bonded to four Ti4+ atoms to form a mixture of distorted edge and corner-sharing NTi4 trigonal pyramids. In the third N3- site, N3- is bonded to four Ti4+ atoms to form distorted NTi4 trigonal pyramids that share a cornercorner with one NTi4 tetrahedra, corners with three NTi4 trigonal pyramids, edges with two equivalent NTi4 trigonal pyramids, and edges with two equivalent OTi4 trigonal pyramids. In the fourth N3- site, N3- is bonded to four Ti4+ atoms to form distorted NTi4 trigonal pyramids that share a cornercorner with one OTi4 trigonal pyramid, corners with two equivalent NTi4 trigonal pyramids, and edges with four NTi4 trigonal pyramids. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti4+ atoms. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti4+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three Ti4+ atoms. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti4+ atoms. In the fifth O2- site, O2- is bonded to four Ti4+ atoms to form distorted OTi4 trigonal pyramids that share a cornercorner with one NTi4 trigonal pyramid, corners with two equivalent OTi4 trigonal pyramids, edges with two equivalent NTi4 tetrahedra, and edges with two equivalent NTi4 trigonal pyramids. In the sixth O2- site, O2- is bonded in a distorted see-saw-like geometry to four Ti4+ atoms.

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2020-07-22. Materials Data on Ti3N2O3 by Materials Project. https://doi.org/10.17188/1289576

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36 MATERIALS SCIENCE↗