DOI: 10.17188/1270911
title: Materials Data on Cu4Bi4S9 by Materials Project

description: Cu4Bi4S9 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are four inequivalent Cu+1.50+ sites. In the first Cu+1.50+ site, Cu+1.50+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with four equivalent BiS5 square pyramids, corners with two equivalent CuS4 tetrahedra, and an edgeedge with one BiS5 square pyramid. There are a spread of Cu–S bond distances ranging from 2.29–2.36 Å. In the second Cu+1.50+ site, Cu+1.50+ is bonded in a distorted trigonal planar geometry to four S2- atoms. There are a spread of Cu–S bond distances ranging from 2.23–3.06 Å. In the third Cu+1.50+ site, Cu+1.50+ is bonded to four S2- atoms to form distorted CuS4 trigonal pyramids that share corners with three equivalent BiS6 octahedra, corners with two equivalent CuS4 trigonal pyramids, and edges with two equivalent CuS4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 2–77°. There are a spread of Cu–S bond distances ranging from 2.26–2.61 Å. In the fourth Cu+1.50+ site, Cu+1.50+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with two equivalent BiS6 octahedra, a cornercorner with one BiS5 square pyramid, corners with two equivalent CuS4 tetrahedra, and an edgeedge with one BiS6 octahedra. The corner-sharing octahedral tilt angles are 30°. There are a spread of Cu–S bond distances ranging from 2.27–2.41 Å. There are four inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to five S2- atoms to form distorted BiS5 square pyramids that share corners with five CuS4 tetrahedra, edges with two equivalent BiS5 square pyramids, and an edgeedge with one CuS4 tetrahedra. There are a spread of Bi–S bond distances ranging from 2.61–3.07 Å. In the second Bi3+ site, Bi3+ is bonded in a 5-coordinate geometry to seven S2- atoms. There are a spread of Bi–S bond distances ranging from 2.65–3.44 Å. In the third Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Bi–S bond distances ranging from 2.69–3.13 Å. In the fourth Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share corners with two equivalent CuS4 tetrahedra, corners with three equivalent CuS4 trigonal pyramids, edges with four equivalent BiS6 octahedra, and an edgeedge with one CuS4 tetrahedra. There are a spread of Bi–S bond distances ranging from 2.73–3.01 Å. There are nine inequivalent S2- sites. In the first S2- site, S2- is bonded to two Cu+1.50+ and two equivalent Bi3+ atoms to form corner-sharing SCu2Bi2 tetrahedra. In the second S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Cu+1.50+ and three Bi3+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to one Cu+1.50+ and three Bi3+ atoms. In the fourth S2- site, S2- is bonded in a 6-coordinate geometry to three Cu+1.50+ and three Bi3+ atoms. In the fifth S2- site, S2- is bonded to three equivalent Cu+1.50+ and three Bi3+ atoms to form distorted edge-sharing SCu3Bi3 octahedra. In the sixth S2- site, S2- is bonded in a 1-coordinate geometry to one Cu+1.50+ and four Bi3+ atoms. In the seventh S2- site, S2- is bonded in a 5-coordinate geometry to five Bi3+ atoms. In the eighth S2- site, S2- is bonded in a 4-coordinate geometry to three Cu+1.50+ and one S2- atom. The S–S bond length is 2.15 Å. In the ninth S2- site, S2- is bonded in a 4-coordinate geometry to one Cu+1.50+, two equivalent Bi3+, and one S2- atom.