Materials Data on Li2FeS2 by Materials Project

Abstract

Li2FeS2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with eight LiS4 tetrahedra, edges with two equivalent LiS4 tetrahedra, and edges with two equivalent FeS4 tetrahedra. There are three shorter (2.49 Å) and one longer (2.50 Å) Li–S bond lengths. In the second Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with eight LiS4 tetrahedra, edges with two equivalent LiS4 tetrahedra, and edges with two equivalent FeS4 tetrahedra. There are one shorter (2.48 Å) and three longer (2.50 Å) Li–S bond lengths. In the third Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with eight LiS4 tetrahedra, edges with two equivalent LiS4 tetrahedra, and edges with two equivalent FeS4 tetrahedra. There are a spread of Li–S bond distances ranging from 2.47–2.52 Å. In the fourth Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with eight LiS4 tetrahedra, edges with two equivalent LiS4 tetrahedra, and edges with two equivalent FeS4 tetrahedra. There are a spread of Li–S bond distances ranging from 2.48–2.52 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with eight LiS4 tetrahedra, edges with two equivalent FeS4 tetrahedra, and edges with four LiS4 tetrahedra. There are a spread of Fe–S bond distances ranging from 2.33–2.35 Å. In the second Fe2+ site, Fe2+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with eight LiS4 tetrahedra, edges with two equivalent FeS4 tetrahedra, and edges with four LiS4 tetrahedra. There are a spread of Fe–S bond distances ranging from 2.33–2.35 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted hexagonal planar geometry to four Li1+ and two Fe2+ atoms. In the second S2- site, S2- is bonded in a distorted hexagonal planar geometry to four Li1+ and two Fe2+ atoms. In the third S2- site, S2- is bonded in a distorted hexagonal planar geometry to four Li1+ and two Fe2+ atoms. In the fourth S2- site, S2- is bonded in a 6-coordinate geometry to four Li1+ and two Fe2+ atoms.