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DOE OSTI · 1312080

Materials Data on Li2Cu2F7 by Materials Project

Abstract

Li2Cu2F7 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 2.00–2.09 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Li–F bond distances ranging from 1.97–2.56 Å. In the third Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Li–F bond distances ranging from 1.97–2.56 Å. In the fourth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 2.00–2.08 Å. There are four inequivalent Cu+2.50+ sites. In the first Cu+2.50+ site, Cu+2.50+ is bonded to six F1- atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedra tilt angles range from 14–34°. There are a spread of Cu–F bond distances ranging from 1.91–1.99 Å. In the second Cu+2.50+ site, Cu+2.50+ is bonded to six F1- atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedra tilt angles range from 16–29°. There are a spread of Cu–F bond distances ranging from 1.89–2.02 Å. In the third Cu+2.50+ site, Cu+2.50+ is bonded to six F1- atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedra tilt angles range from 16–29°. There are a spread of Cu–F bond distances ranging from 1.89–2.02 Å. In the fourth Cu+2.50+ site, Cu+2.50+ is bonded to six F1- atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedra tilt angles range from 14–34°. There are a spread of Cu–F bond distances ranging from 1.91–1.99 Å. There are fourteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a bent 150 degrees geometry to two Cu+2.50+ atoms. In the second F1- site, F1- is bonded to two equivalent Li1+ and two Cu+2.50+ atoms to form distorted FLi2Cu2 trigonal pyramids that share a cornercorner with one FLi3Cu tetrahedra and corners with three FLi2Cu2 trigonal pyramids. In the third F1- site, F1- is bonded in a bent 150 degrees geometry to two Cu+2.50+ atoms. In the fourth F1- site, F1- is bonded to three Li1+ and one Cu+2.50+ atom to form distorted FLi3Cu trigonal pyramids that share corners with two equivalent FLi3Cu tetrahedra, corners with seven FLi2Cu2 trigonal pyramids, and edges with four FLi3Cu tetrahedra. In the fifth F1- site, F1- is bonded in a T-shaped geometry to one Li1+ and two equivalent Cu+2.50+ atoms. In the sixth F1- site, F1- is bonded in a T-shaped geometry to one Li1+ and two equivalent Cu+2.50+ atoms. In the seventh F1- site, F1- is bonded to three Li1+ and one Cu+2.50+ atom to form distorted FLi3Cu tetrahedra that share corners with six FLi3Cu tetrahedra, corners with three FLi2Cu2 trigonal pyramids, and edges with four FLi3Cu trigonal pyramids. In the eighth F1- site, F1- is bonded to three Li1+ and one Cu+2.50+ atom to form a mixture of distorted edge and corner-sharing FLi3Cu tetrahedra. In the ninth F1- site, F1- is bonded in a T-shaped geometry to one Li1+ and two equivalent Cu+2.50+ atoms. In the tenth F1- site, F1- is bonded in a T-shaped geometry to one Li1+ and two equivalent Cu+2.50+ atoms. In the eleventh F1- site, F1- is bonded to three Li1+ and one Cu+2.50+ atom to form a mixture of distorted edge and corner-sharing FLi3Cu trigonal pyramids. In the twelfth F1- site, F1- is bonded to two equivalent Li1+ and two Cu+2.50+ atoms to form distorted corner-sharing FLi2Cu2 trigonal pyramids. In the thirteenth F1- site, F1- is bonded in a bent 150 degrees geometry to two Cu+2.50+ atoms. In the fourteenth F1- site, F1- is bonded in a bent 150 degrees geometry to two Cu+2.50+ atoms.

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2020-06-04. Materials Data on Li2Cu2F7 by Materials Project. https://doi.org/10.17188/1312080

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