Trimeric thioformaldehyde as a ligand: preparation and crystal structure of [Ag₂{(CH₂S)₃}₅][AsF₆]₂·SO₂

The reaction of trimeric thioformaldehyde with AgAsF6 in liquid SO2 leads to the compound [Ag2{(CH2S)3}5][AsF6]2·SO2, which was characterised by X-ray structure determination [space group Pbca, with a= 16.286(3), b= 28.487(5), c= 18.118(3)Å, and Z= 8; R= 0.061 for 5 150 unique observed reflections]. The isolated canons, of the form L2AgLAgL2(L = ligand), display irregular co-ordination geometry at silver; one silver is co-ordinated by four sulphurs from three ligands, the other by five sulphurs from three ligands.