Materials Data on LiFeF3 by Materials Project

Abstract

LiFeF3 is pyrite-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Li1+ is bonded to five F1- atoms to form distorted LiF5 tetrahedra that share corners with six FeF6 octahedra, corners with four equivalent LiF5 tetrahedra, and edges with two FeF6 octahedra. The corner-sharing octahedra tilt angles range from 53–71°. There are a spread of Li–F bond distances ranging from 1.93–2.53 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with two equivalent FeF6 octahedra, corners with six equivalent LiF5 tetrahedra, edges with two equivalent FeF6 octahedra, and edges with two equivalent LiF5 tetrahedra. The corner-sharing octahedral tilt angles are 64°. There are a spread of Fe–F bond distances ranging from 2.08–2.17 Å. In the second Fe2+ site, Fe2+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with two equivalent FeF6 octahedra, corners with six equivalent LiF5 tetrahedra, edges with two equivalent FeF6 octahedra, and edges with two equivalent LiF5 tetrahedra. The corner-sharing octahedral tilt angles are 64°. There are a spread of Fe–F bond distances ranging from 2.05–2.17 Å. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to one Li1+ and two Fe2+ atoms. In the second F1- site, F1- is bonded to two equivalent Li1+ and two Fe2+ atoms to form corner-sharing FLi2Fe2 tetrahedra. In the third F1- site, F1- is bonded in a 4-coordinate geometry to two equivalent Li1+ and two Fe2+ atoms.