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DOE OSTI · 1298836

Materials Data on Li4Ti3Mn6O18 by Materials Project

Abstract

Li4Ti3Mn6O18 crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to five O2- atoms to form distorted LiO5 trigonal bipyramids that share corners with two equivalent MnO6 octahedra, corners with three TiO6 octahedra, an edgeedge with one TiO6 octahedra, edges with three MnO6 octahedra, and edges with two equivalent LiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 9–76°. There are a spread of Li–O bond distances ranging from 2.10–2.47 Å. In the second Li1+ site, Li1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Li–O bond distances ranging from 2.31–2.58 Å. In the third Li1+ site, Li1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.09–2.72 Å. In the fourth Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.19–2.52 Å. There are three inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent MnO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and edges with four TiO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Ti–O bond distances ranging from 1.92–2.07 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent MnO6 octahedra, corners with two equivalent LiO5 trigonal bipyramids, edges with two equivalent TiO6 octahedra, edges with two equivalent MnO6 octahedra, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 49°. There are a spread of Ti–O bond distances ranging from 1.91–2.10 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four MnO5 square pyramids and edges with four TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.92–2.01 Å. There are six inequivalent Mn+3.33+ sites. In the first Mn+3.33+ site, Mn+3.33+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent LiO5 trigonal bipyramids, edges with six MnO6 octahedra, and an edgeedge with one LiO5 trigonal bipyramid. There are a spread of Mn–O bond distances ranging from 1.93–1.96 Å. In the second Mn+3.33+ site, Mn+3.33+ is bonded to five O2- atoms to form MnO5 square pyramids that share corners with two equivalent TiO6 octahedra, corners with four MnO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Mn–O bond distances ranging from 1.96–2.12 Å. In the third Mn+3.33+ site, Mn+3.33+ is bonded to six O2- atoms to form distorted MnO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with two equivalent MnO5 square pyramids, edges with four MnO6 octahedra, and edges with two equivalent LiO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. There are a spread of Mn–O bond distances ranging from 1.96–2.26 Å. In the fourth Mn+3.33+ site, Mn+3.33+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with four MnO5 square pyramids, edges with two equivalent TiO6 octahedra, and edges with two equivalent MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–1.97 Å. In the fifth Mn+3.33+ site, Mn+3.33+ is bonded to five O2- atoms to form MnO5 square pyramids that share corners with two equivalent TiO6 octahedra, corners with four MnO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 51–65°. There are a spread of Mn–O bond distances ranging from 1.95–2.09 Å. In the sixth Mn+3.33+ site, Mn+3.33+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with two equivalent MnO5 square pyramids, and edges with four MnO6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Mn–O bond distances ranging from 1.95–2.26 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Mn+3.33+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Mn+3.33+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to two equivalent Li1+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded to two equivalent Li1+ and three Ti4+ atoms to form distorted OLi2Ti3 trigonal bipyramids that share corners with two equivalent OLiTiMn2 trigonal pyramids and edges with two equivalent OLi2Ti3 trigonal bipyramids. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Li1+ and three Mn+3.33+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+ and three Mn+3.33+ atoms. In the seventh O2- site, O2- is bonded to two equivalent Li1+ and three Mn+3.33+ atoms to form OLi2Mn3 square pyramids that share corners with two equivalent OLi2Mn3 square pyramids, edges with three OLi2Mn3 square pyramids, and edges with two equivalent OLiTiMn2 trigonal pyramids. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Li1+ and three Mn+3.33+ atoms. In the ninth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ti4+ and two equivalent Mn+3.33+ atoms. In the tenth O2- site, O2- is bonded to one Li1+, one Ti4+, and two equivalent Mn+3.33+ atoms to form distorted OLiTiMn2 trigonal pyramids that share corners with two equivalent OLi2Ti3 trigonal bipyramids, corners with two equivalent OLiTiMn2 trigonal pyramids, and edges with two equivalent OLi2Mn3 square pyramids. In the eleventh O2- site, O2- is bonded in a distorted square co-planar geometry to two equivalent Li1+ and two equivalent Ti4+ atoms. In the twelfth O2- site, O2- is bonded to two equivalent Li1+, two equivalent Ti4+, and one Mn+3.33+ atom to form distorted edge-sharing OLi2Ti2Mn trigonal bipyramids. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Li1+ and three Mn+3.33+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent Ti4+, and one Mn+3.33+ atom. In the fifteenth O2- site, O2- is bonded to two equivalent Li1+ and three Mn+3.33+ atoms to form a mixture of distorted edge and corner-sharing OLi2Mn3 square pyramids. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+ and two equivalent Mn+3.33+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Ti4+ atoms. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ti4+, and two equivalent Mn+3.33+ atoms.

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2020-04-29. Materials Data on Li4Ti3Mn6O18 by Materials Project. https://doi.org/10.17188/1298836

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