Materials Data on Si2Ag6O7 by Materials Project

Abstract

Ag6Si2O7 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are five inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to four O2- atoms to form distorted AgO4 tetrahedra that share a cornercorner with one AgO4 tetrahedra, corners with four SiO4 tetrahedra, a cornercorner with one AgO4 trigonal pyramid, and an edgeedge with one AgO4 tetrahedra. There are a spread of Ag–O bond distances ranging from 2.33–2.57 Å. In the second Ag1+ site, Ag1+ is bonded to four O2- atoms to form distorted AgO4 trigonal pyramids that share a cornercorner with one AgO4 tetrahedra, corners with four SiO4 tetrahedra, and an edgeedge with one AgO4 trigonal pyramid. There are a spread of Ag–O bond distances ranging from 2.27–2.51 Å. In the third Ag1+ site, Ag1+ is bonded in a linear geometry to two O2- atoms. There are one shorter (2.08 Å) and one longer (2.10 Å) Ag–O bond lengths. In the fourth Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to two O2- atoms. There are one shorter (2.22 Å) and one longer (2.28 Å) Ag–O bond lengths. In the fifth 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 2.18–2.49 Å. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent AgO4 tetrahedra, corners with two SiO4 tetrahedra, and corners with two equivalent AgO4 trigonal pyramids. There is three shorter (1.64 Å) and one longer (1.66 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent AgO4 tetrahedra and corners with four equivalent AgO4 trigonal pyramids. There is three shorter (1.66 Å) and one longer (1.68 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra, corners with four equivalent AgO4 tetrahedra, and corners with two equivalent AgO4 trigonal pyramids. There is three shorter (1.65 Å) and one longer (1.68 Å) Si–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four Ag1+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Ag1+ and one Si4+ atom. In the fourth O2- site, O2- is bonded to three Ag1+ and one Si4+ atom to form distorted corner-sharing OSiAg3 tetrahedra. In the fifth O2- site, O2- is bonded to three Ag1+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing OSiAg3 tetrahedra. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Ag1+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Ag1+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Si4+ atoms.