Materials Data on FeSi(AgS2)2 by Materials Project

Abstract

Ag2FeSiS4 is Stannite-like structured and crystallizes in the monoclinic Pc space group. The structure is three-dimensional. Fe2+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with four equivalent SiS4 tetrahedra and corners with eight AgS4 tetrahedra. There are a spread of Fe–S bond distances ranging from 2.29–2.34 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to four S2- atoms to form AgS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with four equivalent AgS4 tetrahedra, and corners with four equivalent SiS4 tetrahedra. There are a spread of Ag–S bond distances ranging from 2.54–2.60 Å. In the second Ag1+ site, Ag1+ is bonded to four S2- atoms to form AgS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with four equivalent AgS4 tetrahedra, and corners with four equivalent SiS4 tetrahedra. There are a spread of Ag–S bond distances ranging from 2.56–2.62 Å. Si4+ is bonded to four S2- atoms to form SiS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra and corners with eight AgS4 tetrahedra. There are one shorter (2.15 Å) and three longer (2.16 Å) Si–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to one Fe2+, two Ag1+, and one Si4+ atom to form corner-sharing SFeSiAg2 tetrahedra. In the second S2- site, S2- is bonded to one Fe2+, two Ag1+, and one Si4+ atom to form corner-sharing SFeSiAg2 tetrahedra. In the third S2- site, S2- is bonded to one Fe2+, two Ag1+, and one Si4+ atom to form distorted corner-sharing SFeSiAg2 tetrahedra. In the fourth S2- site, S2- is bonded to one Fe2+, two Ag1+, and one Si4+ atom to form corner-sharing SFeSiAg2 tetrahedra.