Materials Data on Li5FeS4 by Materials Project

Abstract

Li5FeS4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 tetrahedra that share a cornercorner with one FeS6 octahedra, corners with ten LiS4 tetrahedra, edges with two equivalent FeS6 octahedra, and edges with three LiS4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Li–S bond distances ranging from 2.36–2.48 Å. In the second Li1+ site, Li1+ is bonded to four S2- atoms to form LiS4 tetrahedra that share a cornercorner with one FeS6 octahedra, corners with ten LiS4 tetrahedra, edges with two equivalent FeS6 octahedra, and edges with three LiS4 tetrahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Li–S bond distances ranging from 2.36–2.49 Å. In the third Li1+ site, Li1+ is bonded in a square co-planar geometry to four equivalent S2- atoms. All Li–S bond lengths are 2.52 Å. Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with four LiS4 tetrahedra, edges with two equivalent FeS6 octahedra, and edges with eight LiS4 tetrahedra. There are four shorter (2.49 Å) and two longer (2.70 Å) Fe–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to four Li1+ and two equivalent Fe3+ atoms to form a mixture of edge and corner-sharing SLi4Fe2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second S2- site, S2- is bonded in a 7-coordinate geometry to six Li1+ and one Fe3+ atom.