Zero to Three Dimensional Increase of Silver(I) Coordination Assemblies Controlled by Deprotonation of 1,3,5-Tri(2-benzimidazolyl)benzene and Aggregation of Multinuclear Building Units

Four Ag(I) complexes of a triangular multidentate ligand 1,3,5-tri(2-benzimidazolyl)benzene (H3TBimB), namely,
[Ag2(H3TBimB)2](CF3SO3)2 (1), [Ag4(HTBimB)2]n (2), [Ag9(HTBimB)4(TAZ)]n (HTAZ = 1,2,4-triazole) (3), and [Ag17(TBimB)5(HTBimB)(H2O)5]n·nH2O (4), have been synthesized at different pH values adjusted by addition of NH3·H2O under solvothermal conditions and characterized by X-ray single-crystal diffraction. Complex 1 shows an M2L2
dimeric structure, 2 displays a one-dimensional chain containing M4L2 basic units, 3 is a two-dimensional network
built up from an M9L4 subunit, and 4 exhibits a three-dimensional framework generated by an M17L6 motif. Dimensional
increase in complexes 1−4 was caused by deprotonation of the H3TBimB ligand, thus offering more coordinating
donors and resulting in aggregation of oligomeric Ag(I) building units. In the cases of complexes 3 and 4, TAZ or
H2O molecules serve as auxiliary ligands to complete the coordination geometry of the Ag(I) ions wherever necessary.
The photoluminescent properties of the ligand H3TBimB and the complexes 1−3 have been investigated.