Materials Data on Ge(PbS2)2 by Materials Project
Pb2GeS4 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. there are four inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Pb–S bond distances ranging from 2.87–3.59 Å. In the second Pb2+ site, Pb2+ is bonded in a 4-coordinate geometry to four S2- atoms. There are two shorter (2.84 Å) and two longer (2.94 Å) Pb–S bond lengths. In the third Pb2+ site, Pb2+ is bonded to six S2- atoms to form distorted PbS6 pentagonal pyramids that share corners with two equivalent GeS4 tetrahedra and edges with two equivalent GeS4 tetrahedra. There are a spread of Pb–S bond distances ranging from 2.98–3.13 Å. In the fourth Pb2+ site, Pb2+ is bonded in a 4-coordinate geometry to eight S2- atoms. There are a spread of Pb–S bond distances ranging from 2.86–3.58 Å. Ge4+ is bonded to four S2- atoms to form GeS4 tetrahedra that share a cornercorner with one PbS6 pentagonal pyramid and an edgeedge with one PbS6 pentagonal pyramid. There are a spread of Ge–S bond distances ranging from 2.23–2.27 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to three Pb2+ and one Ge4+ atom. In the second S2- site, S2- is bonded in a 1-coordinate geometry to three Pb2+ and one Ge4+ atom. In the third S2- site, S2- is bonded in a 1-coordinate geometry to three Pb2+ and one Ge4+ atom. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to four Pb2+ and one Ge4+ atom.