Materials Data on K2Ag3Sb3S7 by Materials Project
K2Ag3Sb3S7 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. K1+ is bonded in a 10-coordinate geometry to one Ag1+ and nine S2- atoms. The K–Ag bond length is 3.49 Å. There are a spread of K–S bond distances ranging from 3.28–3.63 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a distorted rectangular see-saw-like geometry to four S2- atoms. There are a spread of Ag–S bond distances ranging from 2.46–2.94 Å. In the second Ag1+ site, Ag1+ is bonded in a distorted trigonal planar geometry to one K1+ and three S2- atoms. There are a spread of Ag–S bond distances ranging from 2.48–2.60 Å. There are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three S2- atoms. There are a spread of Sb–S bond distances ranging from 2.43–2.54 Å. In the second Sb3+ site, Sb3+ is bonded in a distorted T-shaped geometry to three S2- atoms. There are one shorter (2.46 Å) and two longer (2.48 Å) Sb–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to four Ag1+ and one Sb3+ atom. In the second S2- site, S2- is bonded in a 6-coordinate geometry to four equivalent K1+ and two equivalent Sb3+ atoms. In the third S2- site, S2- is bonded to four equivalent K1+, one Ag1+, and one Sb3+ atom to form a mixture of distorted edge and corner-sharing SK4AgSb octahedra. The corner-sharing octahedra tilt angles range from 31–49°. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to one K1+, two Ag1+, and one Sb3+ atom.