Materials Data on Li3FeF6 by Materials Project

Abstract

Li3FeF6 is pyrite-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four F1- atoms. There are three shorter (1.99 Å) and one longer (2.09 Å) Li–F bond lengths. In the second Li1+ site, Li1+ is bonded to six F1- atoms to form LiF6 octahedra that share corners with six equivalent FeF6 octahedra. The corner-sharing octahedra tilt angles range from 42–50°. There are a spread of Li–F bond distances ranging from 1.98–2.21 Å. Fe3+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with six equivalent LiF6 octahedra. The corner-sharing octahedra tilt angles range from 42–50°. There is four shorter (1.95 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 to three Li1+ and one Fe3+ atom to form distorted corner-sharing FLi3Fe tetrahedra. In the second F1- site, F1- is bonded in a 3-coordinate geometry to two Li1+ and one Fe3+ atom. In the third F1- site, F1- is bonded in a 3-coordinate geometry to two Li1+ and one Fe3+ atom.