Materials Data on Cu2AgBiPbS4 by Materials Project
AgCu2PbBiS4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ag1+ is bonded in a 4-coordinate geometry to two equivalent Cu1+ and four S2- atoms. Both Ag–Cu bond lengths are 2.71 Å. There are a spread of Ag–S bond distances ranging from 2.52–3.08 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a distorted linear geometry to two equivalent Ag1+ and four S2- atoms. There are a spread of Cu–S bond distances ranging from 2.20–3.07 Å. In the second Cu1+ site, Cu1+ is bonded in a distorted trigonal planar geometry to one Pb2+ and three S2- atoms. The Cu–Pb bond length is 3.00 Å. There are two shorter (2.28 Å) and one longer (2.34 Å) Cu–S bond lengths. Pb2+ is bonded in a 5-coordinate geometry to one Cu1+ and seven S2- atoms. There are a spread of Pb–S bond distances ranging from 2.92–3.39 Å. Bi3+ is bonded to six S2- atoms to form edge-sharing BiS6 octahedra. There are a spread of Bi–S bond distances ranging from 2.76–2.96 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to one Ag1+, two equivalent Pb2+, and three equivalent Bi3+ atoms to form distorted edge-sharing SAgBi3Pb2 octahedra. In the second S2- site, S2- is bonded in a 1-coordinate geometry to two equivalent Ag1+, one Cu1+, two equivalent Pb2+, and one Bi3+ atom. In the third S2- site, S2- is bonded in a 6-coordinate geometry to three Cu1+, one Pb2+, and two equivalent Bi3+ atoms. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to one Ag1+, three Cu1+, and two equivalent Pb2+ atoms.