Materials Data on Li2Cu2F7 by Materials Project

Abstract

Li2Cu2F7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with six CuF6 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–63°. There are a spread of Li–F bond distances ranging from 1.88–1.93 Å. In the second Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with five CuF6 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–58°. There are a spread of Li–F bond distances ranging from 1.88–1.97 Å. There are two inequivalent Cu+2.50+ sites. In the first Cu+2.50+ site, Cu+2.50+ is bonded to six F1- atoms to form CuF6 octahedra that share a cornercorner with one CuF6 octahedra, corners with seven LiF4 tetrahedra, and edges with two equivalent CuF6 octahedra. The corner-sharing octahedral tilt angles are 22°. There are a spread of Cu–F bond distances ranging from 1.92–2.06 Å. In the second Cu+2.50+ site, Cu+2.50+ is bonded to six F1- atoms to form CuF6 octahedra that share a cornercorner with one CuF6 octahedra, corners with four LiF4 tetrahedra, and edges with three CuF6 octahedra. The corner-sharing octahedral tilt angles are 22°. There are a spread of Cu–F bond distances ranging from 1.84–2.13 Å. There are seven inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Cu+2.50+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Cu+2.50+ atoms. In the third F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Cu+2.50+ atoms. In the fourth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Li1+ and one Cu+2.50+ atom. In the fifth F1- site, F1- is bonded in a trigonal planar geometry to one Li1+ and two Cu+2.50+ atoms. In the sixth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Cu+2.50+ atom. In the seventh F1- site, F1- is bonded in a distorted T-shaped geometry to three Cu+2.50+ atoms.