A 2D polymer with unique Ag-C bonds, [Ag(mu(4)-DPOAc)](n) (1) [DPOAc = diphenylacetate], has been synthesized and characterized and its structure was determined by X-ray crystallography. In addition to the coordination to the 0 atoms of DPOAc the Ag atoms also form strong eta(1) Ag-C pi bonds and exhibit weak Ag-Ag interactions, resulting in the formation of O3CAg... AgO3C moieties. The thermal stabilities of 1 and of its thallium(I) analogue, [Tl(mu(3)-DPOAc)](n) (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 370, 383 and 360 nm, respectively. The results of studies of the stoichiometry and formation of complexes of I and 2 in DMF solution were found to be in support of their solid state stoichiometry. (c) 2007 Elsevier B. V. All rights reserved.