Materials Data on LiFe2F6 by Materials Project
LiFe2F6 is Hydrophilite-derived structured and crystallizes in the tetragonal P4_2nm space group. The structure is three-dimensional. Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with eight FeF6 octahedra and edges with two FeF6 octahedra. The corner-sharing octahedra tilt angles range from 46–54°. There are a spread of Li–F bond distances ranging from 2.05–2.11 Å. There are two inequivalent Fe+2.50+ sites. In the first Fe+2.50+ site, Fe+2.50+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with four equivalent LiF6 octahedra, corners with four equivalent FeF6 octahedra, an edgeedge with one LiF6 octahedra, and an edgeedge with one FeF6 octahedra. The corner-sharing octahedra tilt angles range from 47–54°. There are a spread of Fe–F bond distances ranging from 2.06–2.13 Å. In the second Fe+2.50+ site, Fe+2.50+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with four equivalent LiF6 octahedra, corners with four equivalent FeF6 octahedra, an edgeedge with one LiF6 octahedra, and an edgeedge with one FeF6 octahedra. The corner-sharing octahedra tilt angles range from 46–49°. There is four shorter (1.96 Å) and two longer (1.98 Å) Fe–F bond length. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Fe+2.50+ atoms. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Fe+2.50+ atoms. In the third F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Fe+2.50+ atoms.