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DOE OSTI · 1707727

Materials Data on Li4TiV4(Fe2O9)2 by Materials Project

Abstract

Li4TiV4(Fe2O9)2 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 TiO6 octahedra, corners with three VO6 octahedra, an edgeedge with one TiO6 octahedra, an edgeedge with one VO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent LiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 12–80°. There are a spread of Li–O bond distances ranging from 2.09–2.43 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.17–2.63 Å. In the third 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 2.08–2.62 Å. In the fourth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.13–2.60 Å. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent LiO5 trigonal bipyramids, edges with two equivalent TiO6 octahedra, edges with two equivalent VO6 octahedra, and an edgeedge with one LiO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 50°. There are a spread of Ti–O bond distances ranging from 1.91–2.12 Å. There are four inequivalent V+4.25+ sites. In the first V+4.25+ site, V+4.25+ is bonded to six O2- atoms to form VO6 octahedra that share corners with two equivalent LiO5 trigonal bipyramids, edges with two equivalent VO6 octahedra, edges with four FeO6 octahedra, and an edgeedge with one LiO5 trigonal bipyramid. There are a spread of V–O bond distances ranging from 1.91–2.02 Å. In the second V+4.25+ site, V+4.25+ is bonded to six O2- atoms to form VO6 octahedra that share corners with two equivalent FeO6 octahedra, a cornercorner with one LiO5 trigonal bipyramid, and edges with four VO6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of V–O bond distances ranging from 1.87–2.13 Å. In the third V+4.25+ site, V+4.25+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four FeO5 square pyramids, edges with two equivalent TiO6 octahedra, and edges with two equivalent VO6 octahedra. There are a spread of V–O bond distances ranging from 1.87–1.99 Å. In the fourth V+4.25+ site, V+4.25+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four FeO5 square pyramids and edges with four VO6 octahedra. There are a spread of V–O bond distances ranging from 1.91–1.99 Å. There are four inequivalent Fe+2.75+ sites. In the first Fe+2.75+ site, Fe+2.75+ is bonded to five O2- atoms to form FeO5 square pyramids that share corners with two equivalent FeO6 octahedra, corners with four VO6 octahedra, and edges with two equivalent FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 50–62°. There are a spread of Fe–O bond distances ranging from 1.97–2.03 Å. In the second Fe+2.75+ site, Fe+2.75+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent VO6 octahedra, corners with two equivalent FeO5 square pyramids, edges with two equivalent VO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent LiO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 48°. There are a spread of Fe–O bond distances ranging from 1.99–2.13 Å. In the third Fe+2.75+ site, Fe+2.75+ is bonded to five O2- atoms to form FeO5 square pyramids that share corners with two equivalent FeO6 octahedra, corners with four VO6 octahedra, and edges with two equivalent FeO5 square pyramids. The corner-sharing octahedra tilt angles range from 49–67°. There are a spread of Fe–O bond distances ranging from 1.94–1.98 Å. In the fourth Fe+2.75+ site, Fe+2.75+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with two equivalent FeO5 square pyramids, edges with two equivalent VO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Fe–O bond distances ranging from 1.95–2.19 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one V+4.25+ and two equivalent Fe+2.75+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one V+4.25+ and two equivalent Fe+2.75+ atoms. In the third O2- site, O2- is bonded in a distorted 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 V+4.25+ atoms to form distorted OLi2V3 trigonal bipyramids that share corners with two equivalent OLi2Fe3 trigonal bipyramids and edges with three OLi2V3 trigonal bipyramids. In the fifth O2- site, O2- is bonded to two equivalent Li1+ and three Fe+2.75+ atoms to form distorted OLi2Fe3 trigonal bipyramids that share a cornercorner with one OLi2V2Fe square pyramid, corners with two equivalent OLi2V3 trigonal bipyramids, and edges with three OLi2V3 trigonal bipyramids. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, two equivalent V+4.25+, and one Fe+2.75+ atom. In the seventh O2- site, O2- is bonded to two equivalent Li1+, two equivalent V+4.25+, and one Fe+2.75+ atom to form OLi2V2Fe square pyramids that share corners with two equivalent OLi2V2Fe square pyramids, a cornercorner with one OLi2Fe3 trigonal bipyramid, and edges with three OLi2V2Fe square pyramids. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V+4.25+ and two equivalent Fe+2.75+ atoms. In the ninth O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Ti4+ and two equivalent V+4.25+ atoms. In the tenth O2- site, O2- is bonded in a 5-coordinate geometry to two Li1+, one V+4.25+, and two equivalent Fe+2.75+ atoms. In the eleventh O2- site, O2- is bonded in a distorted square co-planar geometry to two equivalent Li1+ and two equivalent V+4.25+ atoms. In the twelfth O2- site, O2- is bonded to two equivalent Li1+, two equivalent Ti4+, and one V+4.25+ atom to form distorted OLi2Ti2V trigonal bipyramids that share corners with two equivalent OLi2Fe3 trigonal bipyramids and edges with five OLi2Ti2V trigonal bipyramids. In the thirteenth O2- site, O2- is bonded to two equivalent Li1+ and three Fe+2.75+ atoms to form distorted OLi2Fe3 trigonal bipyramids that share a cornercorner with one OLi2V2Fe square pyramid, corners with two equivalent OLi2Ti2V trigonal bipyramids, and edges with five OLi2Ti2V trigonal bipyramids. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent V+4.25+, and one Fe+2.75+ atom. In the fifteenth O2- site, O2- is bonded to two equivalent Li1+, two equivalent V+4.25+, and one Fe+2.75+ atom to form OLi2V2Fe square pyramids that share corners with two equivalent OLi2V2Fe square pyramids, a cornercorner with one OLi2Fe3 trigonal bipyramid, edges with three OLi2V2Fe square pyramids, and edges with two equivalent OLi2TiFe2 trigonal bipyramids. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one V+4.25+ and two equivalent Fe+2.75+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three V+4.25+ atoms. In the eighteenth O2- site, O2- is bonded to two Li1+, one Ti4+, and two equivalent Fe+2.75+ atoms to form distorted OLi2TiFe2 trigonal bipyramids that share corners with two equivalent OLi2TiFe2 trigonal bipyramids, edges with two equivalent OLi2V2Fe square pyramids, and edges with four OLi2Fe3 trigonal bipyramids.

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2020-06-05. Materials Data on Li4TiV4(Fe2O9)2 by Materials Project. https://doi.org/10.17188/1707727

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