DOE OSTI2020
Ag8Hg(AsO5)2 crystallizes in the trigonal P31c space group. The structure is three-dimensional. there are four inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Ag–O bond distances ranging from 2.29–2.47 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three equivalent O2- atoms. All Ag–O bond lengths are 2.29 Å. In the third Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three equivalent O2- atoms. All Ag–O bond lengths are 2.31 Å. In the fourth Ag1+ site, Ag1+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are one shorter (2.26 Å) and two longer (2.37 Å) Ag–O bond lengths. Hg2+ is bonded in a linear geometry to two O2- atoms. There are one shorter (2.07 Å) and one longer (2.10 Å) Hg–O bond lengths. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded in a tetrahedral geometry to four O2- atoms. There is three shorter (1.72 Å) and one longer (1.76 Å) As–O bond length. In the second As5+ site, As5+ is bonded in a tetrahedral geometry to four O2- atoms. There is one shorter (1.73 Å) and three longer (1.74 Å) As–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ag1+ and one As5+ atom to form distorted corner-sharing OAg3As tetrahedra. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ag1+ and one As5+ atom. In the third O2- site, O2- is bonded to three equivalent Ag1+ and one Hg2+ atom to form corner-sharing OAg3Hg tetrahedra. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ag1+ and one As5+ atom. In the fifth O2- site, O2- is bonded to three equivalent Ag1+ and one Hg2+ atom to form corner-sharing OAg3Hg tetrahedra. In the sixth O2- site, O2- is bonded to three equivalent Ag1+ and one As5+ atom to form distorted corner-sharing OAg3As tetrahedra.