Probing the frameworks of polymeric of silver(I) nitrate complexes with flexible bisthiadiazole alkanes by tuning the ligand spacers

In this context, three structurally related flexible heterocyclic thioethers involving thiadiazole, 2,2′-[methylenebis(thio)]bis[1,3,4-thiadiazole] (L1), 2,2′-[1,2-ethanediyl bis(thio)]bis[1,3,4-thiadiazole] (L2) and 2,2′-[1,3-propanediylbis(thio)]bis[1,3,4-thiadiazole] (L3), and three new silver nitrate complexes of these ligands, [AgL1(NO3)] 1, [AgL2](NO3)22, and [AgL3(NO3)] 3, have been synthesized and characterized. All six new structures were determined by single-crystal X-ray diffraction analysis. Complexes 1-3 exhibit an infinite three-dimensional structure, 1D zigzag chain structure and quasi-2D structure, respectively. In the crystal structures of the three complexes, a variety of coordination modes of AgI have been observed, probably due to the variation of the chain length of the linker unit. In line with the analysis of the corresponding ligands structures, it is clear that geometrical effects seem to be more important than electronic effects in controlling the framework formation of these systems, resulting in the AgI center to prefer to coordinate to N donors rather than S donors despite AgI being a 'soft' metal.