Materials Data on Hg3(SeBr)2 by Materials Project
Hg3(SeBr)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are five inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to two Se2- and three Br1- atoms to form distorted HgSe2Br3 square pyramids that share corners with two HgSe2Br4 octahedra, a cornercorner with one HgSe2Br3 square pyramid, edges with two HgSe2Br4 octahedra, and an edgeedge with one HgSe2Br3 square pyramid. The corner-sharing octahedra tilt angles range from 59–61°. Both Hg–Se bond lengths are 2.59 Å. There are a spread of Hg–Br bond distances ranging from 2.93–3.52 Å. In the second Hg2+ site, Hg2+ is bonded to two equivalent Se2- and four Br1- atoms to form HgSe2Br4 octahedra that share corners with four equivalent HgSe2Br4 octahedra, corners with two equivalent HgSe2Br3 square pyramids, edges with four HgSe2Br4 octahedra, and edges with two equivalent HgSe2Br3 square pyramids. The corner-sharing octahedra tilt angles range from 4–9°. Both Hg–Se bond lengths are 2.56 Å. There are two shorter (3.33 Å) and two longer (3.35 Å) Hg–Br bond lengths. In the third Hg2+ site, Hg2+ is bonded to two equivalent Se2- and four Br1- atoms to form HgSe2Br4 octahedra that share corners with four equivalent HgSe2Br4 octahedra, corners with two equivalent HgSe2Br3 square pyramids, edges with four HgSe2Br4 octahedra, and edges with two equivalent HgSe2Br3 square pyramids. The corner-sharing octahedra tilt angles range from 4–9°. Both Hg–Se bond lengths are 2.56 Å. There are two shorter (3.25 Å) and two longer (3.42 Å) Hg–Br bond lengths. In the fourth Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to two equivalent Se2- and three Br1- atoms. Both Hg–Se bond lengths are 2.55 Å. There are a spread of Hg–Br bond distances ranging from 3.12–3.39 Å. In the fifth Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to two equivalent Se2- and three Br1- atoms. Both Hg–Se bond lengths are 2.56 Å. There are a spread of Hg–Br bond distances ranging from 3.01–3.66 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three Hg2+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to three Hg2+ atoms. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 5-coordinate geometry to five Hg2+ atoms. In the second Br1- site, Br1- is bonded in a 4-coordinate geometry to seven Hg2+ atoms. In the third Br1- site, Br1- is bonded in a 3-coordinate geometry to three Hg2+ atoms. In the fourth Br1- site, Br1- is bonded in a 5-coordinate geometry to five Hg2+ atoms.