Materials Data on Li2FeS2 by Materials Project
Li2FeS2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Li1+ is bonded to four equivalent S2- atoms to form LiS4 tetrahedra that share corners with six equivalent FeS6 octahedra, corners with six equivalent LiS4 tetrahedra, edges with three equivalent FeS6 octahedra, and edges with three equivalent LiS4 tetrahedra. The corner-sharing octahedra tilt angles range from 11–58°. There are three shorter (2.35 Å) and one longer (2.54 Å) Li–S bond lengths. Fe2+ is bonded to six equivalent S2- atoms to form FeS6 octahedra that share corners with twelve equivalent LiS4 tetrahedra, edges with six equivalent FeS6 octahedra, and edges with six equivalent LiS4 tetrahedra. All Fe–S bond lengths are 2.59 Å. S2- is bonded in a 7-coordinate geometry to four equivalent Li1+ and three equivalent Fe2+ atoms.