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DOE OSTI · 1206709

Materials Data on Li7Ti7O16 by Materials Project

Abstract

Li7Ti7O16 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are five inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with six TiO6 octahedra, edges with four TiO6 octahedra, and edges with six LiO6 octahedra. The corner-sharing octahedra tilt angles range from 1–9°. There are a spread of Li–O bond distances ranging from 2.10–2.32 Å. In the second Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share edges with six equivalent LiO6 octahedra and edges with six TiO6 octahedra. There are three shorter (2.08 Å) and three longer (2.10 Å) Li–O bond lengths. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with twelve TiO6 octahedra. The corner-sharing octahedra tilt angles range from 57–65°. There is one shorter (1.89 Å) and three longer (2.04 Å) Li–O bond length. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with twelve TiO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are three shorter (1.99 Å) and one longer (2.09 Å) Li–O bond lengths. In the fifth Li1+ site, Li1+ is bonded in a distorted trigonal non-coplanar geometry to six O2- atoms. There are three shorter (1.92 Å) and three longer (2.45 Å) Li–O bond lengths. There are three inequivalent Ti+3.57+ sites. In the first Ti+3.57+ site, Ti+3.57+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent LiO6 octahedra, corners with three LiO4 tetrahedra, edges with three LiO6 octahedra, and edges with five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 1–7°. There are a spread of Ti–O bond distances ranging from 1.96–2.07 Å. In the second Ti+3.57+ site, Ti+3.57+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent LiO6 octahedra, corners with three LiO4 tetrahedra, edges with three LiO6 octahedra, and edges with five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 5–9°. There are a spread of Ti–O bond distances ranging from 1.99–2.08 Å. In the third Ti+3.57+ site, Ti+3.57+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six LiO4 tetrahedra and edges with six TiO6 octahedra. There are three shorter (1.97 Å) and three longer (2.06 Å) Ti–O bond lengths. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and two equivalent Ti+3.57+ atoms to form OLi3Ti2 square pyramids that share corners with three equivalent OLi4Ti2 octahedra, corners with two equivalent OLi3Ti2 square pyramids, corners with four equivalent OLiTi3 tetrahedra, edges with five OLi3Ti3 octahedra, edges with two equivalent OLi3Ti2 square pyramids, and an edgeedge with one OLiTi3 trigonal pyramid. The corner-sharing octahedra tilt angles range from 0–7°. In the second O2- site, O2- is bonded to one Li1+ and three equivalent Ti+3.57+ atoms to form distorted OLiTi3 trigonal pyramids that share corners with three equivalent OLi3Ti3 octahedra, corners with six equivalent OLiTi3 tetrahedra, and edges with three equivalent OLi3Ti2 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the third O2- site, O2- is bonded to one Li1+ and three Ti+3.57+ atoms to form distorted OLiTi3 tetrahedra that share corners with four equivalent OLi3Ti2 square pyramids, corners with two equivalent OLiTi3 tetrahedra, corners with three OLiTi3 trigonal pyramids, an edgeedge with one OLi3Ti3 octahedra, and edges with two equivalent OLiTi3 tetrahedra. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+ and three Ti+3.57+ atoms. In the fifth O2- site, O2- is bonded to three equivalent Li1+ and three equivalent Ti+3.57+ atoms to form OLi3Ti3 octahedra that share corners with three equivalent OLi3Ti3 octahedra, corners with three equivalent OLiTi3 trigonal pyramids, edges with three equivalent OLi4Ti2 octahedra, edges with six equivalent OLi3Ti2 square pyramids, and edges with three equivalent OLiTi3 tetrahedra. The corner-sharing octahedral tilt angles are 9°. In the sixth O2- site, O2- is bonded to three equivalent Li1+ and three equivalent Ti+3.57+ atoms to form OLi3Ti3 octahedra that share corners with three equivalent OLi3Ti3 octahedra, corners with three equivalent OLiTi3 trigonal pyramids, edges with six equivalent OLi4Ti2 octahedra, and edges with three equivalent OLi3Ti2 square pyramids. The corner-sharing octahedral tilt angles are 9°. In the seventh O2- site, O2- is bonded to four Li1+ and two equivalent Ti+3.57+ atoms to form OLi4Ti2 octahedra that share corners with three equivalent OLi3Ti2 square pyramids, edges with seven OLi3Ti3 octahedra, edges with two equivalent OLi3Ti2 square pyramids, and an edgeedge with one OLiTi3 trigonal pyramid. In the eighth O2- site, O2- is bonded to one Li1+ and three equivalent Ti+3.57+ atoms to form distorted OLiTi3 trigonal pyramids that share corners with three equivalent OLi3Ti3 octahedra, corners with three equivalent OLiTi3 tetrahedra, and edges with three equivalent OLi4Ti2 octahedra. The corner-sharing octahedral tilt angles are 0°.

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2020-05-02. Materials Data on Li7Ti7O16 by Materials Project. https://doi.org/10.17188/1206709

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