Materials Data on Li2FeF6 by Materials Project
Li2FeF6 is zeta iron carbide-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Li is bonded to six F atoms to form LiF6 octahedra that share corners with six equivalent FeF6 octahedra and edges with three equivalent LiF6 octahedra. The corner-sharing octahedra tilt angles range from 42–49°. There are a spread of Li–F bond distances ranging from 1.97–2.30 Å. Fe is bonded to six F atoms to form FeF6 octahedra that share corners with twelve equivalent LiF6 octahedra. The corner-sharing octahedra tilt angles range from 42–49°. There is two shorter (1.81 Å) and four longer (1.92 Å) Fe–F bond length. There are two inequivalent F sites. In the first F site, F is bonded in a 3-coordinate geometry to two equivalent Li and one Fe atom. In the second F site, F is bonded in a distorted T-shaped geometry to two equivalent Li and one Fe atom.