Materials Data on LiFe2O2F3 by Materials Project

Abstract

LiFe2O2F3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Li1+ is bonded to two equivalent O2- and four F1- atoms to form LiO2F4 octahedra that share corners with two equivalent LiO2F4 octahedra, corners with six equivalent FeO3F3 octahedra, and edges with four equivalent FeO3F3 octahedra. The corner-sharing octahedra tilt angles range from 43–62°. Both Li–O bond lengths are 2.15 Å. There are two shorter (2.03 Å) and two longer (2.06 Å) Li–F bond lengths. Fe3+ is bonded to three equivalent O2- and three F1- atoms to form FeO3F3 octahedra that share corners with three equivalent LiO2F4 octahedra, corners with four equivalent FeO3F3 octahedra, an edgeedge with one FeO3F3 octahedra, edges with two equivalent LiO2F4 octahedra, and a faceface with one FeO3F3 octahedra. The corner-sharing octahedra tilt angles range from 43–48°. There are a spread of Fe–O bond distances ranging from 1.92–1.94 Å. There are a spread of Fe–F bond distances ranging from 1.95–2.05 Å. O2- is bonded to one Li1+ and three equivalent Fe3+ atoms to form a mixture of edge and corner-sharing OLiFe3 trigonal pyramids. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted T-shaped geometry to one Li1+ and two equivalent Fe3+ atoms. In the second F1- site, F1- is bonded in a 4-coordinate geometry to two equivalent Li1+ and two equivalent Fe3+ atoms.