DOI: 10.17188/1283869
title: Materials Data on Tl7Bi3I16 by Materials Project

description: Tl7Bi3I16 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are eight inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 9-coordinate geometry to nine I1- atoms. There are a spread of Tl–I bond distances ranging from 3.74–3.86 Å. In the second Tl1+ site, Tl1+ is bonded in a 8-coordinate geometry to eight I1- atoms. There are a spread of Tl–I bond distances ranging from 3.49–3.90 Å. In the third Tl1+ site, Tl1+ is bonded to seven I1- atoms to form distorted TlI7 pentagonal bipyramids that share corners with two equivalent BiI6 octahedra, corners with two TlI7 pentagonal bipyramids, and edges with four BiI6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Tl–I bond distances ranging from 3.56–3.68 Å. In the fourth Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to eight I1- atoms. There are a spread of Tl–I bond distances ranging from 3.59–4.30 Å. In the fifth Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to eight I1- atoms. There are a spread of Tl–I bond distances ranging from 3.65–4.16 Å. In the sixth Tl1+ site, Tl1+ is bonded in a 9-coordinate geometry to nine I1- atoms. There are a spread of Tl–I bond distances ranging from 3.71–4.20 Å. In the seventh Tl1+ site, Tl1+ is bonded in a 8-coordinate geometry to eight I1- atoms. There are a spread of Tl–I bond distances ranging from 3.58–3.85 Å. In the eighth Tl1+ site, Tl1+ is bonded to seven I1- atoms to form distorted TlI7 pentagonal bipyramids that share corners with two equivalent BiI6 octahedra, corners with two equivalent TlI7 pentagonal bipyramids, and edges with four equivalent BiI6 octahedra. The corner-sharing octahedral tilt angles are 48°. All Tl–I bond lengths are 3.61 Å. There are four inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six I1- atoms to form BiI6 octahedra that share a cornercorner with one TlI7 pentagonal bipyramid, an edgeedge with one BiI6 octahedra, and edges with two TlI7 pentagonal bipyramids. There are a spread of Bi–I bond distances ranging from 2.98–3.28 Å. In the second Bi3+ site, Bi3+ is bonded in an octahedral geometry to six I1- atoms. There are a spread of Bi–I bond distances ranging from 3.03–3.16 Å. In the third Bi3+ site, Bi3+ is bonded to six I1- atoms to form BiI6 octahedra that share a cornercorner with one TlI7 pentagonal bipyramid, an edgeedge with one BiI6 octahedra, and edges with two equivalent TlI7 pentagonal bipyramids. There are a spread of Bi–I bond distances ranging from 2.98–3.26 Å. In the fourth Bi3+ site, Bi3+ is bonded in an octahedral geometry to six I1- atoms. There are two shorter (3.04 Å) and four longer (3.12 Å) Bi–I bond lengths. There are sixteen inequivalent I1- sites. In the first I1- site, I1- is bonded to four Tl1+ and one Bi3+ atom to form a mixture of distorted edge and corner-sharing ITl4Bi square pyramids. In the second I1- site, I1- is bonded in a 5-coordinate geometry to four Tl1+ and one Bi3+ atom. In the third I1- site, I1- is bonded in a 1-coordinate geometry to three Tl1+ and one Bi3+ atom. In the fourth I1- site, I1- is bonded in a 1-coordinate geometry to four Tl1+ and one Bi3+ atom. In the fifth I1- site, I1- is bonded in a 4-coordinate geometry to three Tl1+ and one Bi3+ atom. In the sixth I1- site, I1- is bonded in a distorted rectangular see-saw-like geometry to two Tl1+ and two equivalent Bi3+ atoms. In the seventh I1- site, I1- is bonded to four Tl1+ and one Bi3+ atom to form distorted ITl4Bi trigonal bipyramids that share corners with six ITl4Bi trigonal bipyramids, corners with two equivalent ITl2Bi2 trigonal pyramids, an edgeedge with one ITl4Bi square pyramid, edges with four ITl4Bi trigonal bipyramids, and an edgeedge with one ITl2Bi2 trigonal pyramid. In the eighth I1- site, I1- is bonded to two equivalent Tl1+ and two equivalent Bi3+ atoms to form distorted ITl2Bi2 trigonal pyramids that share corners with four equivalent ITl4Bi trigonal bipyramids, corners with two equivalent ITl2Bi2 trigonal pyramids, and edges with four equivalent ITl4Bi trigonal bipyramids. In the ninth I1- site, I1- is bonded in a 4-coordinate geometry to three Tl1+ and one Bi3+ atom. In the tenth I1- site, I1- is bonded to four Tl1+ and one Bi3+ atom to form a mixture of distorted edge and corner-sharing ITl4Bi trigonal bipyramids. In the eleventh I1- site, I1- is bonded in a 5-coordinate geometry to three Tl1+ and two equivalent Bi3+ atoms. In the twelfth I1- site, I1- is bonded to four Tl1+ and one Bi3+ atom to form distorted ITl4Bi trigonal bipyramids that share a cornercorner with one ITl4Bi square pyramid, corners with five ITl4Bi trigonal bipyramids, edges with four ITl4Bi trigonal bipyramids, and an edgeedge with one ITl2Bi2 trigonal pyramid. In the thirteenth I1- site, I1- is bonded in a 5-coordinate geometry to four Tl1+ and one Bi3+ atom. In the fourteenth I1- site, I1- is bonded in a 5-coordinate geometry to four Tl1+ and one Bi3+ atom. In the fifteenth I1- site, I1- is bonded to two Tl1+ and two equivalent Bi3+ atoms to form distorted ITl2Bi2 trigonal pyramids that share corners with six ITl4Bi trigonal bipyramids, a cornercorner with one ITl2Bi2 trigonal pyramid, and edges with four ITl4Bi trigonal bipyramids. In the sixteenth I1- site, I1- is bonded to four Tl1+ and one Bi3+ atom to form distorted ITl4Bi trigonal bipyramids that share corners with two equivalent ITl4Bi square pyramids, corners with four ITl4Bi trigonal bipyramids, corners with two ITl2Bi2 trigonal pyramids, edges with five ITl4Bi trigonal bipyramids, and an edgeedge with one ITl2Bi2 trigonal pyramid.