A 3D polymer built with the assistance of η2 Ag–C bonds, [Ag2(μ8-SB)] (1) [H2SB=4-[(4-hydroxyphenyl)sulfonyl]-1-benzenol], has been synthesized and characterized and its structure was determined by X-ray crystallography. In addition to the coordination to the O atoms of SB2− the Ag atoms also form strong η2 Ag–C bonds, resulting in the formation of an AgO2C2 environment. The thermal stabilities of 1 and of its thallium(I) analogue, [Tl4(μ8-SB)2] (2), were studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The ligand and compounds 1–2 are luminescent in the solution state, with emission maxima at 380, 353 and 468nm, respectively. The results of studies of the stoichiometry and formation of complexes of 1 and 2 in acetonitrile and DMF solutions were found to be in support of their solid state stoichiometry.