Materials Data on LiFeF4 by Materials Project

Abstract

LiFeF4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with six FeF4 tetrahedra and edges with two equivalent LiF6 octahedra. There are a spread of Li–F bond distances ranging from 2.01–2.16 Å. In the second Li1+ site, Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with six FeF4 tetrahedra and edges with three LiF6 octahedra. There are a spread of Li–F bond distances ranging from 1.97–2.21 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four F1- atoms to form FeF4 tetrahedra that share corners with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 16–60°. There are a spread of Fe–F bond distances ranging from 1.83–1.87 Å. In the second Fe3+ site, Fe3+ is bonded to four F1- atoms to form FeF4 tetrahedra that share corners with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 20–59°. There is two shorter (1.84 Å) and two longer (1.86 Å) Fe–F bond length. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded to three Li1+ and one Fe3+ atom to form distorted edge-sharing FLi3Fe trigonal pyramids. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to one Li1+ and one Fe3+ atom. In the third F1- site, F1- is bonded in a bent 150 degrees geometry to one Li1+ and one Fe3+ atom. In the fourth F1- site, F1- is bonded in a linear geometry to one Li1+ and one Fe3+ atom. In the fifth F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one Fe3+ atom.