Materials Data on Nb2Tl5S4Br9 by Materials Project
Nb2Tl5S4Br9 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Nb5+ is bonded in a 8-coordinate geometry to four equivalent S2- and four Br1- atoms. All Nb–S bond lengths are 2.51 Å. There are two shorter (2.71 Å) and two longer (2.80 Å) Nb–Br bond lengths. There are two inequivalent Tl+1.40+ sites. In the first Tl+1.40+ site, Tl+1.40+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of Tl–Br bond distances ranging from 3.29–3.77 Å. In the second Tl+1.40+ site, Tl+1.40+ is bonded to six Br1- atoms to form corner-sharing TlBr6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (3.30 Å) and two longer (3.73 Å) Tl–Br bond lengths. S2- is bonded in a 5-coordinate geometry to two equivalent Nb5+ atoms. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted single-bond geometry to one Nb5+ and four equivalent Tl+1.40+ atoms. In the second Br1- site, Br1- is bonded in a 3-coordinate geometry to one Nb5+ and four Tl+1.40+ atoms. In the third Br1- site, Br1- is bonded to six Tl+1.40+ atoms to form corner-sharing BrTl6 octahedra. The corner-sharing octahedral tilt angles are 0°.