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DOE OSTI · 1294867

Materials Data on Li2CrF4 by Materials Project

Abstract

Li2CrF4 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are eight inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to five F1- atoms to form LiF5 square pyramids that share a cornercorner with one LiF6 octahedra, corners with two CrF6 octahedra, corners with two equivalent LiF5 square pyramids, an edgeedge with one LiF6 octahedra, edges with two equivalent CrF6 octahedra, and edges with two equivalent LiF5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 18–71°. There are a spread of Li–F bond distances ranging from 1.84–2.07 Å. In the second Li1+ site, Li1+ is bonded to five F1- atoms to form LiF5 trigonal bipyramids that share corners with two CrF6 octahedra, corners with three LiF6 octahedra, corners with two equivalent LiF5 trigonal bipyramids, edges with two equivalent LiF6 octahedra, edges with two equivalent CrF6 octahedra, and edges with two equivalent LiF5 square pyramids. The corner-sharing octahedra tilt angles range from 0–74°. There are a spread of Li–F bond distances ranging from 1.91–2.32 Å. In the third Li1+ site, Li1+ is bonded to six F1- atoms to form distorted LiF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent CrF6 octahedra, a cornercorner with one LiF5 square pyramid, edges with three CrF6 octahedra, and edges with five LiF6 octahedra. The corner-sharing octahedra tilt angles range from 4–18°. There are a spread of Li–F bond distances ranging from 1.92–2.55 Å. In the fourth Li1+ site, Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent CrF6 octahedra, a cornercorner with one LiF5 trigonal bipyramid, edges with three CrF6 octahedra, and edges with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 9–22°. There are a spread of Li–F bond distances ranging from 1.95–2.25 Å. In the fifth Li1+ site, Li1+ is bonded to six F1- atoms to form distorted LiF6 octahedra that share corners with two equivalent CrF6 octahedra, corners with four LiF6 octahedra, edges with three CrF6 octahedra, and edges with five LiF6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Li–F bond distances ranging from 2.05–2.67 Å. In the sixth Li1+ site, Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent CrF6 octahedra, edges with three CrF6 octahedra, and edges with eight LiF6 octahedra. The corner-sharing octahedra tilt angles range from 7–15°. There are a spread of Li–F bond distances ranging from 2.04–2.15 Å. In the seventh Li1+ site, Li1+ is bonded to six F1- atoms to form distorted LiF6 octahedra that share corners with four LiF6 octahedra, corners with two equivalent LiF5 trigonal bipyramids, edges with five LiF6 octahedra, and edges with five CrF6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Li–F bond distances ranging from 2.04–2.65 Å. In the eighth Li1+ site, Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent CrF6 octahedra, edges with three LiF6 octahedra, edges with three CrF6 octahedra, an edgeedge with one LiF5 square pyramid, and edges with two equivalent LiF5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 10–17°. There are a spread of Li–F bond distances ranging from 1.94–2.15 Å. There are four inequivalent Cr2+ sites. In the first Cr2+ site, Cr2+ is bonded to six F1- atoms to form distorted CrF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent CrF6 octahedra, a cornercorner with one LiF5 trigonal bipyramid, an edgeedge with one CrF6 octahedra, edges with three LiF6 octahedra, and edges with two equivalent LiF5 square pyramids. The corner-sharing octahedra tilt angles range from 7–20°. There are a spread of Cr–F bond distances ranging from 2.01–2.40 Å. In the second Cr2+ site, Cr2+ is bonded to six F1- atoms to form CrF6 octahedra that share corners with two equivalent CrF6 octahedra, corners with four LiF6 octahedra, a cornercorner with one LiF5 square pyramid, an edgeedge with one CrF6 octahedra, edges with five LiF6 octahedra, and edges with two equivalent LiF5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 4–18°. There are a spread of Cr–F bond distances ranging from 2.04–2.45 Å. In the third Cr2+ site, Cr2+ is bonded to six F1- atoms to form distorted CrF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent CrF6 octahedra, a cornercorner with one LiF5 square pyramid, an edgeedge with one CrF6 octahedra, and edges with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 7–15°. There are a spread of Cr–F bond distances ranging from 1.98–2.47 Å. In the fourth Cr2+ site, Cr2+ is bonded to six F1- atoms to form CrF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent CrF6 octahedra, a cornercorner with one LiF5 trigonal bipyramid, an edgeedge with one CrF6 octahedra, and edges with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 9–18°. There are a spread of Cr–F bond distances ranging from 1.98–2.41 Å. There are sixteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a T-shaped geometry to one Li1+ and two Cr2+ atoms. In the second F1- site, F1- is bonded in a rectangular see-saw-like geometry to three Li1+ and one Cr2+ atom. In the third F1- site, F1- is bonded in a see-saw-like geometry to two Li1+ and two equivalent Cr2+ atoms. In the fourth F1- site, F1- is bonded to four Li1+ and one Cr2+ atom to form distorted FLi4Cr trigonal bipyramids that share corners with two equivalent FLi4Cr2 octahedra, a cornercorner with one FLi4Cr square pyramid, corners with two equivalent FLi4Cr trigonal bipyramids, a cornercorner with one FLi2Cr2 trigonal pyramid, and edges with four FLi3Cr2 square pyramids. The corner-sharing octahedra tilt angles range from 2–3°. In the fifth F1- site, F1- is bonded to four Li1+ and one Cr2+ atom to form distorted FLi4Cr square pyramids that share corners with three FLi4Cr square pyramids, an edgeedge with one FLi5Cr octahedra, and edges with four FLi4Cr square pyramids. In the sixth F1- site, F1- is bonded to three Li1+ and two equivalent Cr2+ atoms to form distorted FLi3Cr2 square pyramids that share corners with five FLi4Cr square pyramids, edges with three FLi4Cr2 octahedra, edges with two equivalent FLi4Cr square pyramids, and edges with two equivalent FLi4Cr trigonal bipyramids. In the seventh F1- site, F1- is bonded to four Li1+ and one Cr2+ atom to form distorted FLi4Cr square pyramids that share corners with two equivalent FLi4Cr square pyramids, a cornercorner with one FLi4Cr trigonal bipyramid, a cornercorner with one FLi2Cr2 trigonal pyramid, edges with three FLi4Cr2 octahedra, and edges with five FLi4Cr square pyramids. In the eighth F1- site, F1- is bonded in a distorted T-shaped geometry to one Li1+ and two Cr2+ atoms. In the ninth F1- site, F1- is bonded to four Li1+ and two Cr2+ atoms to form distorted FLi4Cr2 octahedra that share corners with two equivalent FLi4Cr2 octahedra, corners with two equivalent FLi4Cr square pyramids, corners with two equivalent FLi4Cr trigonal bipyramids, edges with two equivalent FLi5Cr octahedra, edges with five FLi3Cr2 square pyramids, and an edgeedge with one FLi2Cr2 trigonal pyramid. The corner-sharing octahedral tilt angles are 6°. In the tenth F1- site, F1- is bonded to four Li1+ and one Cr2+ atom to form distorted FLi4Cr square pyramids that share corners with two equivalent FLi4Cr2 octahedra, corners with two equivalent FLi4Cr square pyramids, a cornercorner with one FLi2Cr2 trigonal pyramid, edges with two equivalent FLi5Cr octahedra, and edges with three FLi4Cr square pyramids. The corner-sharing octahedra tilt angles range from 4–11°. In the eleventh F1- site, F1- is bonded in a distorted square co-planar geometry to two Li1+ and two equivalent Cr2+ atoms. In the twelfth F1- site, F1- is bonded to five Li1+ and one Cr2+ atom to form FLi5Cr octahedra that share corners with two equivalent FLi5Cr octahedra, edges with two equivalent FLi4Cr2 octahedra, edges with seven FLi4Cr square pyramids, and edges with two equivalent FLi2Cr2 trigonal pyramids. The corner-sharing octahedral tilt angles are 7°. In the thirteenth F1- site, F1- is bonded in a distorted T-shaped geometry to two Li1+ and one Cr2+ atom. In the fourteenth F1- site, F1- is bonded to two Li1+ and two equivalent Cr2+ atoms to form FLi2Cr2 trigonal pyramids that share corners with two FLi4Cr square pyramids, a cornercorner with one FLi4Cr trigonal bipyramid, corners with two equivalent FLi2Cr2 trigonal pyramids, edges with three FLi4Cr2 octahedra, and edges with two equivalent FLi4Cr square pyramids. In the fifteenth F1- site, F1- is bonded to four Li1+ and one Cr2+ atom to form FLi4Cr square pyramids that share corners with four FLi3Cr2 square pyramids, edges with three FLi5Cr octahedra, edges with two equivalent FLi4Cr trigonal bipyramids, and edges with two equivalent FLi2Cr2 trigonal pyramids. In the sixteenth F1- site, F1- is bonded in a T-shaped geometry to one Li1+ and two Cr2+ atoms.

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2020-04-29. Materials Data on Li2CrF4 by Materials Project. https://doi.org/10.17188/1294867

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