Adaptable metal cluster block: Facile construction of photoluminescent CuI coordination polymeric clusters with metal (I) iodides

Solution reaction of Cu(I) iodide with organic multifunctional ligands generated two different structure motifs: 0D cluster [(CuI)2(dpds)2] 1 (dpds = 2,2′-dipyridyldisulfide), and 1D polymer [(CuI)(bbbm)]n 2 (bbbm = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole). Both compounds contain the flexible rhomboid Cu2I2 cluster unit. The solution-state luminescence spectra showed that the high-energy emission may be associated with a metal-to-ligand [Cu → π∗(pyridine)] or ligand-to-ligand [I− → π∗(pyridine)] charge-transfer excited state.