Materials Data on LiFeF4 by Materials Project

Abstract

LiFeF4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with four equivalent FeF6 octahedra and an edgeedge with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–57°. There are a spread of Li–F bond distances ranging from 1.86–1.97 Å. Fe3+ is bonded to six F1- atoms to form distorted FeF6 octahedra that share corners with two equivalent FeF6 octahedra, corners with four equivalent LiF4 tetrahedra, and edges with two equivalent FeF6 octahedra. The corner-sharing octahedral tilt angles are 29°. There are a spread of Fe–F bond distances ranging from 1.85–2.32 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Li1+ and one Fe3+ atom. In the second F1- site, F1- is bonded in a 3-coordinate geometry to three equivalent Fe3+ atoms. In the third F1- site, F1- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one Fe3+ atom. In the fourth F1- site, F1- is bonded in a distorted trigonal planar geometry to two equivalent Li1+ and one Fe3+ atom.