Materials Data on Li2Cu2S3 by Materials Project

Abstract

Li2Cu2S3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to five S2- atoms to form distorted LiS5 trigonal bipyramids that share corners with five LiS6 octahedra, corners with six CuS4 tetrahedra, corners with two equivalent LiS5 trigonal bipyramids, edges with three CuS4 tetrahedra, edges with two equivalent LiS5 trigonal bipyramids, and a faceface with one LiS6 octahedra. The corner-sharing octahedra tilt angles range from 31–55°. There are a spread of Li–S bond distances ranging from 2.44–3.02 Å. In the second Li1+ site, Li1+ is bonded to six S2- atoms to form LiS6 octahedra that share corners with eight CuS4 tetrahedra, corners with four equivalent LiS5 trigonal bipyramids, edges with three equivalent LiS6 octahedra, edges with four CuS4 tetrahedra, and faces with two equivalent LiS5 trigonal bipyramids. There are a spread of Li–S bond distances ranging from 2.61–2.69 Å. In the third Li1+ site, Li1+ is bonded to six S2- atoms to form LiS6 octahedra that share corners with six CuS4 tetrahedra, corners with six equivalent LiS5 trigonal bipyramids, edges with five LiS6 octahedra, and edges with six CuS4 tetrahedra. There are a spread of Li–S bond distances ranging from 2.62–2.76 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with three LiS6 octahedra, corners with five CuS4 tetrahedra, corners with two equivalent LiS5 trigonal bipyramids, edges with three LiS6 octahedra, an edgeedge with one CuS4 tetrahedra, and edges with two equivalent LiS5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 18–54°. There are a spread of Cu–S bond distances ranging from 2.26–2.29 Å. In the second Cu2+ site, Cu2+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with four LiS6 octahedra, corners with three equivalent CuS4 tetrahedra, corners with four equivalent LiS5 trigonal bipyramids, edges with two LiS6 octahedra, edges with two CuS4 tetrahedra, and an edgeedge with one LiS5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 20–55°. There are a spread of Cu–S bond distances ranging from 2.26–2.32 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 7-coordinate geometry to four Li1+ and three Cu2+ atoms. In the second S2- site, S2- is bonded in a 6-coordinate geometry to three Li1+ and three Cu2+ atoms. In the third S2- site, S2- is bonded to four Li1+ and two Cu2+ atoms to form a mixture of distorted edge, face, and corner-sharing SLi4Cu2 pentagonal pyramids.