Materials Data on LiCu2F5 by Materials Project
LiCu2F5 crystallizes in the orthorhombic Pnma space group. The structure is two-dimensional and consists of two LiCu2F5 sheets oriented in the (0, 0, 1) direction. Li1+ is bonded to five F1- atoms to form distorted LiF5 square pyramids that share edges with four equivalent CuF6 octahedra and edges with two equivalent LiF5 square pyramids. There are a spread of Li–F bond distances ranging from 2.02–2.42 Å. Cu2+ is bonded to six F1- atoms to form distorted CuF6 octahedra that share corners with two equivalent CuF6 octahedra, edges with five equivalent CuF6 octahedra, and edges with two equivalent LiF5 square pyramids. The corner-sharing octahedral tilt angles are 19°. There are a spread of Cu–F bond distances ranging from 1.86–2.54 Å. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded to one Li1+ and four equivalent Cu2+ atoms to form distorted edge-sharing FLiCu4 square pyramids. In the second F1- site, F1- is bonded in a 3-coordinate geometry to three equivalent Cu2+ atoms. In the third F1- site, F1- is bonded in a trigonal non-coplanar geometry to two equivalent Li1+ and one Cu2+ atom.