DOI: 10.17188/1274705
title: Materials Data on Hg9Bi2(AsBr3)4 by Materials Project

description: Hg9Bi2(AsBr3)4 crystallizes in the tetragonal P4_3 space group. The structure is three-dimensional. there are nine inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to two As3- and two Br1- atoms. Both Hg–As bond lengths are 2.54 Å. There are one shorter (3.22 Å) and one longer (3.38 Å) Hg–Br bond lengths. In the second Hg2+ site, Hg2+ is bonded to two As3- and three Br1- atoms to form distorted HgAs2Br3 square pyramids that share a cornercorner with one BiBr6 octahedra, a cornercorner with one HgAs2Br3 trigonal bipyramid, and an edgeedge with one BiBr6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are one shorter (2.55 Å) and one longer (2.56 Å) Hg–As bond lengths. There are a spread of Hg–Br bond distances ranging from 3.25–3.46 Å. In the third Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to one As3- and three Br1- atoms. The Hg–As bond length is 2.52 Å. There are a spread of Hg–Br bond distances ranging from 2.51–3.36 Å. In the fourth Hg2+ site, Hg2+ is bonded in a distorted see-saw-like geometry to two As3- and two Br1- atoms. There are one shorter (2.55 Å) and one longer (2.56 Å) Hg–As bond lengths. There are one shorter (3.33 Å) and one longer (3.49 Å) Hg–Br bond lengths. In the fifth Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to two As3- and three Br1- atoms. There are one shorter (2.55 Å) and one longer (2.56 Å) Hg–As bond lengths. There are a spread of Hg–Br bond distances ranging from 3.28–3.69 Å. In the sixth Hg2+ site, Hg2+ is bonded in a 3-coordinate geometry to one As3- and two Br1- atoms. The Hg–As bond length is 2.53 Å. There are one shorter (2.55 Å) and one longer (3.22 Å) Hg–Br bond lengths. In the seventh Hg2+ site, Hg2+ is bonded to two As3- and three Br1- atoms to form HgAs2Br3 trigonal bipyramids that share corners with three BiBr6 octahedra and a cornercorner with one HgAs2Br3 square pyramid. The corner-sharing octahedra tilt angles range from 56–73°. There are one shorter (2.56 Å) and one longer (2.57 Å) Hg–As bond lengths. There are a spread of Hg–Br bond distances ranging from 3.25–3.39 Å. In the eighth Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to two As3- and three Br1- atoms. Both Hg–As bond lengths are 2.56 Å. There are a spread of Hg–Br bond distances ranging from 3.37–3.57 Å. In the ninth Hg2+ site, Hg2+ is bonded in a 3-coordinate geometry to two As3- and four Br1- atoms. There are one shorter (2.56 Å) and one longer (2.57 Å) Hg–As bond lengths. There are a spread of Hg–Br bond distances ranging from 3.16–3.72 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six Br1- atoms to form BiBr6 octahedra that share a cornercorner with one BiBr6 octahedra, a cornercorner with one HgAs2Br3 square pyramid, and a cornercorner with one HgAs2Br3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 52°. There are a spread of Bi–Br bond distances ranging from 2.73–3.32 Å. In the second Bi3+ site, Bi3+ is bonded to six Br1- atoms to form BiBr6 octahedra that share a cornercorner with one BiBr6 octahedra, corners with two equivalent HgAs2Br3 trigonal bipyramids, and an edgeedge with one HgAs2Br3 square pyramid. The corner-sharing octahedral tilt angles are 52°. There are a spread of Bi–Br bond distances ranging from 2.82–3.09 Å. There are four inequivalent As3- sites. In the first As3- site, As3- is bonded to four Hg2+ atoms to form corner-sharing AsHg4 tetrahedra. In the second As3- site, As3- is bonded to four Hg2+ atoms to form corner-sharing AsHg4 tetrahedra. In the third As3- site, As3- is bonded to four Hg2+ atoms to form corner-sharing AsHg4 tetrahedra. In the fourth As3- site, As3- is bonded to four Hg2+ atoms to form corner-sharing AsHg4 tetrahedra. There are twelve inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one Bi3+ atom. In the second Br1- site, Br1- is bonded in a 1-coordinate geometry to two Hg2+ and one Bi3+ atom. In the third Br1- site, Br1- is bonded in a 4-coordinate geometry to two Hg2+ and two Bi3+ atoms. In the fourth Br1- site, Br1- is bonded in a distorted water-like geometry to one Hg2+ and one Bi3+ atom. In the fifth Br1- site, Br1- is bonded in a 5-coordinate geometry to four Hg2+ and one Bi3+ atom. In the sixth Br1- site, Br1- is bonded in a 4-coordinate geometry to three Hg2+ and one Bi3+ atom. In the seventh Br1- site, Br1- is bonded in a 2-coordinate geometry to two Hg2+ and one Bi3+ atom. In the eighth Br1- site, Br1- is bonded in a 4-coordinate geometry to two Hg2+ and one Bi3+ atom. In the ninth Br1- site, Br1- is bonded in a 5-coordinate geometry to four Hg2+ and one Bi3+ atom. In the tenth Br1- site, Br1- is bonded in a distorted water-like geometry to two Hg2+ atoms. In the eleventh Br1- site, Br1- is bonded in a distorted single-bond geometry to one Hg2+ and one Bi3+ atom. In the twelfth Br1- site, Br1- is bonded in a 1-coordinate geometry to two Hg2+ and one Bi3+ atom.