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DOE OSTI · 1271249

Materials Data on AgHgSBr by Materials Project

Abstract

AgHgSBr crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Ag1+ is bonded to two equivalent S2- and two Br1- atoms to form distorted AgS2Br2 tetrahedra that share corners with two equivalent HgS2Br4 octahedra, corners with two equivalent AgS2Br2 tetrahedra, edges with two equivalent HgS2Br4 octahedra, and an edgeedge with one AgS2Br2 tetrahedra. The corner-sharing octahedral tilt angles are 61°. Both Ag–S bond lengths are 2.55 Å. There are one shorter (2.73 Å) and one longer (3.00 Å) Ag–Br bond lengths. There are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a distorted rectangular see-saw-like geometry to two equivalent S2- and two equivalent Br1- atoms. Both Hg–S bond lengths are 2.42 Å. Both Hg–Br bond lengths are 3.16 Å. In the second Hg2+ site, Hg2+ is bonded to two equivalent S2- and four equivalent Br1- atoms to form distorted HgS2Br4 octahedra that share corners with four equivalent HgS2Br4 octahedra, corners with four equivalent AgS2Br2 tetrahedra, edges with four equivalent HgS2Br4 octahedra, and edges with four equivalent AgS2Br2 tetrahedra. The corner-sharing octahedral tilt angles are 12°. Both Hg–S bond lengths are 2.41 Å. All Hg–Br bond lengths are 3.43 Å. S2- is bonded to two equivalent Ag1+ and two Hg2+ atoms to form corner-sharing SAg2Hg2 trigonal pyramids. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 4-coordinate geometry to two equivalent Ag1+ and two equivalent Hg2+ atoms. In the second Br1- site, Br1- is bonded in a 6-coordinate geometry to two equivalent Ag1+ and four equivalent Hg2+ atoms.

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2020-07-14. Materials Data on AgHgSBr by Materials Project. https://doi.org/10.17188/1271249

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36 MATERIALS SCIENCE↗