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DOE OSTI · 1274110

Materials Data on AgHg3As2Cl3 by Materials Project

Abstract

AgHg3As2Cl3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to four Cl1- atoms to form distorted AgCl4 trigonal pyramids that share corners with four HgAs2Cl4 octahedra and edges with four HgAs2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 62–63°. There are two shorter (2.49 Å) and two longer (2.91 Å) Ag–Cl bond lengths. In the second Ag1+ site, Ag1+ is bonded in a rectangular see-saw-like geometry to four Cl1- atoms. There are a spread of Ag–Cl bond distances ranging from 2.50–2.86 Å. There are six inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to two As2- and four Cl1- atoms to form HgAs2Cl4 octahedra that share corners with six HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, edges with two HgAs2Cl4 octahedra, and an edgeedge with one AgCl4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 0–88°. Both Hg–As bond lengths are 2.57 Å. There are a spread of Hg–Cl bond distances ranging from 3.16–3.27 Å. In the second Hg2+ site, Hg2+ is bonded in a 6-coordinate geometry to two equivalent As2- and four Cl1- atoms. Both Hg–As bond lengths are 2.58 Å. There are two shorter (2.84 Å) and two longer (3.49 Å) Hg–Cl bond lengths. In the third Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to two As2- and two Cl1- atoms. There are one shorter (2.57 Å) and one longer (2.58 Å) Hg–As bond lengths. There are one shorter (2.83 Å) and one longer (2.95 Å) Hg–Cl bond lengths. In the fourth Hg2+ site, Hg2+ is bonded to two As2- and four Cl1- atoms to form distorted HgAs2Cl4 octahedra that share corners with six HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, a cornercorner with one AgCl4 trigonal pyramid, and edges with two HgAs2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 0–88°. Both Hg–As bond lengths are 2.56 Å. There are a spread of Hg–Cl bond distances ranging from 3.11–3.44 Å. In the fifth Hg2+ site, Hg2+ is bonded to two equivalent As2- and four Cl1- atoms to form HgAs2Cl4 octahedra that share corners with six HgAs2Cl4 octahedra, corners with two equivalent AsHg3As tetrahedra, corners with two equivalent AgCl4 trigonal pyramids, and edges with two equivalent HgAs2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 27–87°. Both Hg–As bond lengths are 2.55 Å. There are two shorter (3.26 Å) and two longer (3.30 Å) Hg–Cl bond lengths. In the sixth Hg2+ site, Hg2+ is bonded to two equivalent As2- and four Cl1- atoms to form HgAs2Cl4 octahedra that share corners with six HgAs2Cl4 octahedra, corners with two equivalent AsHg3As tetrahedra, edges with two equivalent HgAs2Cl4 octahedra, and edges with two equivalent AgCl4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 26–87°. Both Hg–As bond lengths are 2.57 Å. There are two shorter (3.17 Å) and two longer (3.22 Å) Hg–Cl bond lengths. There are three inequivalent As2- sites. In the first As2- site, As2- is bonded to three Hg2+ and one As2- atom to form AsHg3As tetrahedra that share corners with two HgAs2Cl4 octahedra, corners with three AsHg3As tetrahedra, and an edgeedge with one ClAg2Hg4 octahedra. The corner-sharing octahedra tilt angles range from 72–74°. The As–As bond length is 2.43 Å. In the second As2- site, As2- is bonded to three Hg2+ and one As2- atom to form AsHg3As tetrahedra that share a cornercorner with one ClAg2Hg4 octahedra, corners with two HgAs2Cl4 octahedra, and corners with three AsHg3As tetrahedra. The corner-sharing octahedra tilt angles range from 72–80°. The As–As bond length is 2.44 Å. In the third As2- site, As2- is bonded to three Hg2+ and one As2- atom to form AsHg3As tetrahedra that share a cornercorner with one ClAg2Hg4 octahedra, corners with two HgAs2Cl4 octahedra, and corners with three AsHg3As tetrahedra. The corner-sharing octahedra tilt angles range from 73–81°. There are five inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 2-coordinate geometry to one Ag1+ and three Hg2+ atoms. In the second Cl1- site, Cl1- is bonded to two equivalent Ag1+ and four Hg2+ atoms to form ClAg2Hg4 octahedra that share corners with four AsHg3As tetrahedra and edges with two equivalent AsHg3As tetrahedra. In the third Cl1- site, Cl1- is bonded in a 5-coordinate geometry to two Ag1+ and three Hg2+ atoms. In the fourth Cl1- site, Cl1- is bonded in a 1-coordinate geometry to one Ag1+ and four Hg2+ atoms. In the fifth Cl1- site, Cl1- is bonded in a 5-coordinate geometry to one Ag1+ and four Hg2+ atoms.

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2020-07-15. Materials Data on AgHg3As2Cl3 by Materials Project. https://doi.org/10.17188/1274110

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