DOE OSTI2020
Li4TiO4 is Aluminum carbonitride-like structured and crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are sixteen inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with two TiO4 tetrahedra, corners with five LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one TiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.89–2.20 Å. In the second Li1+ site, Li1+ is bonded in a distorted trigonal planar geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.93–2.40 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two LiO4 tetrahedra, corners with two TiO4 tetrahedra, corners with three LiO4 trigonal pyramids, an edgeedge with one TiO4 tetrahedra, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.91–2.02 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with three LiO4 tetrahedra, corners with four TiO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.89–2.28 Å. In the fifth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with two TiO4 tetrahedra, corners with five LiO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one TiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.85–2.58 Å. In the sixth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent TiO4 tetrahedra, corners with three LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one TiO4 tetrahedra, and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.92–2.01 Å. In the seventh Li1+ site, Li1+ is bonded in a 4-coordinate geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.93–2.06 Å. In the eighth Li1+ site, Li1+ is bonded in a 3-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.82–2.60 Å. In the ninth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with three LiO4 tetrahedra, corners with four TiO4 tetrahedra, corners with two equivalent LiO4 trigonal pyramids, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.90–2.17 Å. In the tenth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two TiO4 tetrahedra, corners with four LiO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, an edgeedge with one LiO4 tetrahedra, an edgeedge with one TiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.90–2.15 Å. In the eleventh Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two TiO4 tetrahedra, corners with six LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one TiO4 tetrahedra, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.85–2.11 Å. In the twelfth Li1+ site, Li1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.88–2.20 Å. In the thirteenth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two TiO4 tetrahedra, corners with three LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one LiO4 tetrahedra, an edgeedge with one TiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.93–2.15 Å. In the fourteenth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with four LiO4 tetrahedra, corners with four TiO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, and edges with two LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.89–2.16 Å. In the fifteenth Li1+ site, Li1+ is bonded in a distorted trigonal planar geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.87–2.19 Å. In the sixteenth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two LiO4 tetrahedra, corners with two equivalent TiO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, an edgeedge with one LiO4 tetrahedra, an edgeedge with one TiO4 tetrahedra, and edges with two LiO4 trigonal pyramids. There are a spread of Li–O bond distances ranging from 1.81–2.04 Å. There are four inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 tetrahedra that share corners with six LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Ti–O bond distances ranging from 1.81–1.89 Å. In the second Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 tetrahedra that share corners with three LiO4 tetrahedra, corners with two LiO4 trigonal pyramids, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Ti–O bond distances ranging from 1.79–1.88 Å. In the third Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 tetrahedra that share corners with seven LiO4 tetrahedra, corners with three LiO4 trigonal pyramids, and edges with three LiO4 tetrahedra. There are a spread of Ti–O bond distances ranging from 1.83–1.85 Å. In the fourth Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 tetrahedra that share corners with four LiO4 tetrahedra, a cornercorner with one LiO4 trigonal pyramid, and an edgeedge with one LiO4 tetrahedra. There are a spread of Ti–O bond distances ranging from 1.82–1.85 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded to four Li1+ and one Ti4+ atom to form distorted OLi4Ti trigonal bipyramids that share a cornercorner with one OLi5Ti octahedra, corners with two equivalent OLi4Ti trigonal bipyramids, corners with two OLi3Ti trigonal pyramids, edges with two OLi5Ti octahedra, and an edgeedge with one OLi3Ti trigonal pyramid. The corner-sharing octahedral tilt angles are 56°. In the second O2- site, O2- is bonded to three Li1+ and one Ti4+ atom to form distorted OLi3Ti trigonal pyramids that share corners with two OLi5Ti octahedra, a cornercorner with one OLi3Ti tetrahedra, a cornercorner with one OLi4Ti trigonal bipyramid, a cornercorner with one OLi3Ti trigonal pyramid, and edges with two OLi4Ti trigonal bipyramids. The corner-sharing octahedra tilt angles range from 46–65°. In the third O2- site, O2- is bonded to three Li1+ and one Ti4+ atom to form OLi3Ti trigonal pyramids that share a cornercorner with one OLi3Ti tetrahedra, corners with three OLi4Ti trigonal bipyramids, a cornercorner with one OLi3Ti trigonal pyramid, and an edgeedge with one OLi4Ti trigonal bipyramid. In the fourth O2- site, O2- is bonded to four Li1+ and one Ti4+ atom to form distorted OLi4Ti trigonal bipyramids that share corners with two equivalent OLi4Ti trigonal bipyramids, a cornercorner with one OLi3Ti trigonal pyramid, an edgeedge with one OLi4Ti trigonal bipyramid, and edges with two OLi3Ti trigonal pyramids. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one Ti4+ atom. In the sixth O2- site, O2- is bonded in a see-saw-like geometry to three Li1+ and one Ti4+ atom. In the seventh O2- site, O2- is bonded to four Li1+ and one Ti4+ atom to form OLi4Ti trigonal bipyramids that share corners with two OLi5Ti octahedra, a cornercorner with one OLi3Ti trigonal pyramid, and an edgeedge with one OLi4Ti trigonal bipyramid. The corner-sharing octahedra tilt angles range from 51–57°. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to four Li1+ and one Ti4+ atom. In the ninth O2- site, O2- is bonded in a 6-coordinate geometry to five Li1+ and one Ti4+ atom. In the tenth O2- site, O2- is bonded in a 6-coordinate geometry to five Li1+ and one Ti4+ atom. In the eleventh O2- site, O2- is bonded to five Li1+ and one Ti4+ atom to form distorted OLi5Ti octahedra that share a cornercorner with one OLi3Ti tetrahedra, a cornercorner with one OLi4Ti trigonal bipyramid, a cornercorner with one OLi3Ti trigonal pyramid, edges with two equivalent OLi5Ti octahedra, and an edgeedge with one OLi4Ti trigonal bipyramid. In the twelfth O2- site, O2- is bonded to five Li1+ and one Ti4+ atom to form distorted OLi5Ti octahedra that share corners with two OLi4Ti trigonal bipyramids, a cornercorner with one OLi3Ti trigonal pyramid, edges with two equivalent OLi5Ti octahedra, and an edgeedge with one OLi4Ti trigonal bipyramid. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Li1+ and one Ti4+ atom. In the fourteenth O2- site, O2- is bonded in a 5-coordinate geometry to four Li1+ and one Ti4+ atom. In the fifteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Li1+ and one Ti4+ atom. In the sixteenth O2- site, O2- is bonded to three Li1+ and one Ti4+ atom to form distorted OLi3Ti tetrahedra that share a cornercorner with one OLi5Ti octahedra and corners with two OLi3Ti trigonal pyramids. The corner-sharing octahedral tilt angles are 49°.