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DOE OSTI · 1282709

Materials Data on Ti20H2N17 by Materials Project

Abstract

Ti20N17H2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are ten inequivalent Ti+2.45+ sites. In the first Ti+2.45+ site, Ti+2.45+ is bonded to six N3- atoms to form TiN6 octahedra that share corners with two TiH2N4 octahedra, corners with two equivalent TiN5 square pyramids, edges with eight TiN6 octahedra, and an edgeedge with one TiN5 square pyramid. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Ti–N bond distances ranging from 2.11–2.15 Å. In the second Ti+2.45+ site, Ti+2.45+ is bonded in a rectangular see-saw-like geometry to four N3- atoms. There are two shorter (2.06 Å) and two longer (2.10 Å) Ti–N bond lengths. In the third Ti+2.45+ site, Ti+2.45+ is bonded to five N3- atoms to form TiN5 square pyramids that share corners with five TiN6 octahedra, edges with six TiN6 octahedra, and edges with two equivalent TiN5 square pyramids. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Ti–N bond distances ranging from 2.06–2.12 Å. In the fourth Ti+2.45+ site, Ti+2.45+ is bonded to five N3- and one H1+ atom to form TiHN5 octahedra that share corners with five TiN6 octahedra, edges with ten TiN6 octahedra, and edges with two equivalent TiN5 square pyramids. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Ti–N bond distances ranging from 2.07–2.13 Å. The Ti–H bond length is 2.18 Å. In the fifth Ti+2.45+ site, Ti+2.45+ is bonded to four N3- and two equivalent H1+ atoms to form TiH2N4 octahedra that share corners with six TiN6 octahedra and edges with twelve TiHN5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ti–N bond distances ranging from 2.08–2.11 Å. Both Ti–H bond lengths are 2.16 Å. In the sixth Ti+2.45+ site, Ti+2.45+ is bonded to four N3- and two equivalent H1+ atoms to form TiH2N4 octahedra that share corners with five TiH2N4 octahedra, a cornercorner with one TiN5 square pyramid, and edges with twelve TiHN5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are two shorter (2.08 Å) and two longer (2.11 Å) Ti–N bond lengths. Both Ti–H bond lengths are 2.17 Å. In the seventh Ti+2.45+ site, Ti+2.45+ is bonded to five N3- and one H1+ atom to form TiHN5 octahedra that share corners with six TiHN5 octahedra and edges with twelve TiH2N4 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ti–N bond distances ranging from 2.09–2.13 Å. The Ti–H bond length is 2.14 Å. In the eighth Ti+2.45+ site, Ti+2.45+ is bonded to six N3- atoms to form a mixture of corner and edge-sharing TiN6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ti–N bond distances ranging from 2.10–2.15 Å. In the ninth Ti+2.45+ site, Ti+2.45+ is bonded to six N3- atoms to form TiN6 octahedra that share corners with five TiHN5 octahedra, edges with ten TiHN5 octahedra, and edges with two equivalent TiN5 square pyramids. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Ti–N bond distances ranging from 2.11–2.14 Å. In the tenth Ti+2.45+ site, Ti+2.45+ is bonded to six N3- atoms to form TiN6 octahedra that share corners with four TiN6 octahedra, corners with two equivalent TiN5 square pyramids, edges with nine TiN6 octahedra, and an edgeedge with one TiN5 square pyramid. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Ti–N bond distances ranging from 2.12–2.14 Å. There are nine inequivalent N3- sites. In the first N3- site, N3- is bonded to six Ti+2.45+ atoms to form NTi6 octahedra that share corners with three NTi6 octahedra, corners with three equivalent HTi6 octahedra, an edgeedge with one HTi6 octahedra, and edges with eleven NTi6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the second N3- site, N3- is bonded to six Ti+2.45+ atoms to form NTi6 octahedra that share corners with two equivalent HTi6 octahedra, corners with four NTi6 octahedra, an edgeedge with one HTi6 octahedra, and edges with eleven NTi6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the third N3- site, N3- is bonded to six Ti+2.45+ atoms to form NTi6 octahedra that share corners with six NTi6 octahedra, edges with two equivalent HTi6 octahedra, and edges with ten NTi6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fourth N3- site, N3- is bonded to six Ti+2.45+ atoms to form NTi6 octahedra that share a cornercorner with one HTi6 octahedra, corners with five NTi6 octahedra, and edges with ten NTi6 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the fifth N3- site, N3- is bonded to six Ti+2.45+ atoms to form a mixture of corner and edge-sharing NTi6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the sixth N3- site, N3- is bonded to six Ti+2.45+ atoms to form NTi6 octahedra that share corners with five NTi6 octahedra, edges with two equivalent HTi6 octahedra, and edges with ten NTi6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. In the seventh N3- site, N3- is bonded to six Ti+2.45+ atoms to form NTi6 octahedra that share corners with six NTi6 octahedra, edges with two equivalent HTi6 octahedra, and edges with ten NTi6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. In the eighth N3- site, N3- is bonded to six Ti+2.45+ atoms to form NTi6 octahedra that share corners with six NTi6 octahedra, edges with four equivalent HTi6 octahedra, and edges with eight NTi6 octahedra. The corner-sharing octahedra tilt angles range from 2–3°. In the ninth N3- site, N3- is bonded to six Ti+2.45+ atoms to form a mixture of corner and edge-sharing NTi6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. H1+ is bonded to six Ti+2.45+ atoms to form HTi6 octahedra that share corners with six NTi6 octahedra, edges with two equivalent HTi6 octahedra, and edges with ten NTi6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°.

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2020-04-30. Materials Data on Ti20H2N17 by Materials Project. https://doi.org/10.17188/1282709

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