Effect of anions on the framework formation of novel AgI coordination polymers with angular bridging ligands

Coordination networks based on the organic ligand 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (L-1) or 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (L-2) and various inorganic silver(I) salts were prepared and characterized by single-crystal X-ray analysis. Reaction of AgPF6 or AgClO4.H2O and L-1 in CH3OH/CHCl3 medium afforded a unique two-dimensional coordination polymer {[Ag(L-1)] (PF6)}(infinity) (1) or {[Ag(L-1)] (ClO4)}(infinity) (2) with (2/4,3) topology. However, with the replacement of AgPF6 or AgClO4-H2O with AgNO3 in the above reaction, an interesting three-dimensional coordination architecture {[Ag-4(L-1)(4)(NO3)(2)] (NO3)(2)}(infinity) (3) constructed through weak interactions between nitrate ions and two different one-dimensional motifs was obtained. Furthermore, two one-dimensional coordination chains {[AgL1](CF3SO3)}(infinity) (4) and {[Ag(L-2)] (CF3SO3)}(infinity) (5), with different structural geometries, were obtained by the reactions of AgCF3SO3 with L-1 and L-2, respectively. The structural diversities of these complexes demonstrate that counteranions play essential roles in the construction of such supramolecular frameworks.