DOE OSTI2020
Au2Ag6Se3S crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Au1+ sites. In the first Au1+ site, Au1+ is bonded in a 8-coordinate geometry to six Ag1+, one Se2-, and one S2- atom. There are a spread of Au–Ag bond distances ranging from 3.04–3.14 Å. The Au–Se bond length is 2.51 Å. The Au–S bond length is 2.37 Å. In the second Au1+ site, Au1+ is bonded in a 8-coordinate geometry to six Ag1+ and two Se2- atoms. There are a spread of Au–Ag bond distances ranging from 3.07–3.13 Å. There are one shorter (2.50 Å) and one longer (2.51 Å) Au–Se bond lengths. There are eight inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two equivalent Au1+, two equivalent Se2-, and two equivalent S2- atoms. Both Ag–Se bond lengths are 2.77 Å. Both Ag–S bond lengths are 2.89 Å. In the second Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two equivalent Au1+ and four Se2- atoms. There are two shorter (2.76 Å) and two longer (2.90 Å) Ag–Se bond lengths. In the third Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two equivalent Au1+ and four Se2- atoms. There are two shorter (2.77 Å) and two longer (2.90 Å) Ag–Se bond lengths. In the fourth Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to two equivalent Au1+, two equivalent Se2-, and two equivalent S2- atoms. Both Ag–Se bond lengths are 2.93 Å. Both Ag–S bond lengths are 2.73 Å. In the fifth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two Au1+, three Se2-, and one S2- atom. There are a spread of Ag–Se bond distances ranging from 2.75–2.93 Å. The Ag–S bond length is 2.86 Å. In the sixth Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to two Au1+, three Se2-, and one S2- atom. There are a spread of Ag–Se bond distances ranging from 2.77–2.94 Å. The Ag–S bond length is 2.71 Å. In the seventh Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two Au1+, three Se2-, and one S2- atom. There are two shorter (2.76 Å) and one longer (2.94 Å) Ag–Se bond lengths. The Ag–S bond length is 2.85 Å. In the eighth Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to two Au1+, three Se2-, and one S2- atom. There are a spread of Ag–Se bond distances ranging from 2.78–2.93 Å. The Ag–S bond length is 2.71 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 7-coordinate geometry to one Au1+ and six Ag1+ atoms. In the second Se2- site, Se2- is bonded in a 7-coordinate geometry to one Au1+ and six Ag1+ atoms. In the third Se2- site, Se2- is bonded in a 7-coordinate geometry to one Au1+ and six Ag1+ atoms. S2- is bonded in a 7-coordinate geometry to one Au1+ and six Ag1+ atoms.