Materials Data on Sr2TlBr5 by Materials Project

Abstract

TlSr2Br5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of Sr–Br bond distances ranging from 3.16–3.38 Å. In the second Sr2+ site, Sr2+ is bonded to seven Br1- atoms to form distorted edge-sharing SrBr7 pentagonal bipyramids. There are a spread of Sr–Br bond distances ranging from 3.04–3.25 Å. Tl1+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of Tl–Br bond distances ranging from 3.24–3.88 Å. There are five inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to two equivalent Sr2+ and two equivalent Tl1+ atoms to form distorted BrSr2Tl2 trigonal pyramids that share corners with six BrSr3Tl2 square pyramids, corners with six BrSr2Tl2 trigonal pyramids, edges with three BrSr3Tl2 square pyramids, and an edgeedge with one BrSr2Tl2 trigonal pyramid. In the second Br1- site, Br1- is bonded in a 5-coordinate geometry to three Sr2+ and two equivalent Tl1+ atoms. In the third Br1- site, Br1- is bonded to three Sr2+ and two equivalent Tl1+ atoms to form distorted BrSr3Tl2 square pyramids that share corners with eight BrSr3Tl2 square pyramids, corners with four BrSr2Tl2 trigonal pyramids, an edgeedge with one BrSr3Tl2 square pyramid, edges with four BrSr4 trigonal pyramids, and a faceface with one BrSr3Tl2 square pyramid. In the fourth Br1- site, Br1- is bonded to three Sr2+ and two equivalent Tl1+ atoms to form distorted BrSr3Tl2 square pyramids that share corners with four equivalent BrSr3Tl2 square pyramids, corners with eight BrSr2Tl2 trigonal pyramids, edges with three BrSr3Tl2 square pyramids, edges with two BrSr2Tl2 trigonal pyramids, and a faceface with one BrSr3Tl2 square pyramid. In the fifth Br1- site, Br1- is bonded to four Sr2+ atoms to form distorted BrSr4 trigonal pyramids that share corners with six BrSr3Tl2 square pyramids, corners with six BrSr2Tl2 trigonal pyramids, edges with three BrSr3Tl2 square pyramids, and an edgeedge with one BrSr4 trigonal pyramid.