DOI: 10.17188/1276335
title: Materials Data on TlHg3Sb2Br3 by Materials Project

description: Hg3TlSb2Br3 crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. there are three inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to two equivalent Sb2- and three Br1- atoms to form distorted HgSb2Br3 trigonal bipyramids that share corners with two equivalent TlBr6 octahedra, corners with four equivalent HgSb2Br4 octahedra, corners with two equivalent SbHg3Sb tetrahedra, corners with two equivalent HgSb2Br3 trigonal bipyramids, and edges with two equivalent TlBr6 octahedra. The corner-sharing octahedra tilt angles range from 66–99°. Both Hg–Sb bond lengths are 2.76 Å. There are one shorter (2.92 Å) and two longer (3.46 Å) Hg–Br bond lengths. In the second Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to two equivalent Sb2- and two Br1- atoms. Both Hg–Sb bond lengths are 2.76 Å. There are one shorter (2.92 Å) and one longer (2.93 Å) Hg–Br bond lengths. In the third Hg2+ site, Hg2+ is bonded to two equivalent Sb2- and four Br1- atoms to form HgSb2Br4 octahedra that share corners with four equivalent HgSb2Br4 octahedra, corners with two equivalent SbHg3Sb tetrahedra, corners with four equivalent HgSb2Br3 trigonal bipyramids, and edges with four equivalent TlBr6 octahedra. The corner-sharing octahedra tilt angles range from 23–24°. Both Hg–Sb bond lengths are 2.75 Å. All Hg–Br bond lengths are 3.45 Å. Tl1+ is bonded to six Br1- atoms to form distorted TlBr6 octahedra that share corners with six equivalent TlBr6 octahedra, corners with two equivalent HgSb2Br3 trigonal bipyramids, edges with four equivalent HgSb2Br4 octahedra, and edges with two equivalent HgSb2Br3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 18–23°. There are a spread of Tl–Br bond distances ranging from 3.19–3.66 Å. Sb2- is bonded to three Hg2+ and one Sb2- atom to form SbHg3Sb tetrahedra that share a cornercorner with one HgSb2Br4 octahedra, corners with six BrTl2Hg3 square pyramids, corners with three equivalent SbHg3Sb tetrahedra, a cornercorner with one HgSb2Br3 trigonal bipyramid, and corners with three equivalent BrTl2Hg3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 76°. The Sb–Sb bond length is 2.82 Å. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to three Hg2+ and two equivalent Tl1+ atoms to form distorted BrTl2Hg3 square pyramids that share corners with six BrTl2Hg3 square pyramids, corners with six equivalent SbHg3Sb tetrahedra, corners with three equivalent BrTl2Hg3 trigonal bipyramids, edges with two equivalent BrTl2Hg3 square pyramids, and an edgeedge with one BrTl2Hg3 trigonal bipyramid. In the second Br1- site, Br1- is bonded to three Hg2+ and two equivalent Tl1+ atoms to form distorted BrTl2Hg3 trigonal bipyramids that share corners with three equivalent BrTl2Hg3 square pyramids, corners with six equivalent SbHg3Sb tetrahedra, corners with four equivalent BrTl2Hg3 trigonal bipyramids, and edges with five BrTl2Hg3 square pyramids. In the third Br1- site, Br1- is bonded to three Hg2+ and two equivalent Tl1+ atoms to form distorted BrTl2Hg3 square pyramids that share corners with six BrTl2Hg3 square pyramids, corners with six equivalent SbHg3Sb tetrahedra, edges with two equivalent BrTl2Hg3 square pyramids, and edges with four equivalent BrTl2Hg3 trigonal bipyramids.