Materials Data on TlPb8Br9O4 by Materials Project
TlPb8O4Br9 crystallizes in the tetragonal P4/n space group. The structure is three-dimensional. Tl1+ is bonded in a body-centered cubic geometry to eight Br1- atoms. There are four shorter (3.54 Å) and four longer (3.56 Å) Tl–Br bond lengths. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a distorted single-bond geometry to one O2- and six Br1- atoms. The Pb–O bond length is 2.31 Å. There are a spread of Pb–Br bond distances ranging from 2.93–3.60 Å. In the second Pb2+ site, Pb2+ is bonded in a 3-coordinate geometry to three equivalent O2- and three Br1- atoms. There are a spread of Pb–O bond distances ranging from 2.33–2.40 Å. There are a spread of Pb–Br bond distances ranging from 3.34–3.53 Å. O2- is bonded to four Pb2+ and one Br1- atom to form a mixture of distorted edge, face, and corner-sharing OPb4Br tetrahedra. The O–Br bond length is 3.46 Å. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 5-coordinate geometry to one Tl1+ and four Pb2+ atoms. In the second Br1- site, Br1- is bonded in a 1-coordinate geometry to one Tl1+ and three Pb2+ atoms. In the third Br1- site, Br1- is bonded in a 12-coordinate geometry to eight Pb2+ and four equivalent O2- atoms.