Silver(I) complexes with a bulky acridine-based carboxylic ligand: Syntheses, crystal structures, and luminescent properties

Two new Silver(I) complexes, {[AgL]·(H2O)2}n (1, HL = acridine-9-carboxylic acid) and {[Ag(L)(4,4′-bipy)]·(H2O)5}n (2), has been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction analysis. Ag(I) ion in complex 1 is coordinated by L as a bridging ligand with its acridine N donor and bidentate chelating carboxylate group forming a 1D chain. Different from 1, complex 2 adopts a 1D chain structure with 4,4′-bipy as a bridging ligand. In 2, L coordinates to Ag(I) ion as a terminal ligand by its carboxylate group in a bidentate chelating mode similar to that in 1, leaving N donor as a H-bond acceptor. It is worth noting that in 1 C-H⋯Ag weak interactions are observed, and these weak interactions are also elucidated by theoretical investigation of TD-DFT (B3LYP) methods and NBO analysis. Furthermore, the photoluminescence properties of 1 and 2 are also investigated in the solid state at room temperature, and the theoretical calculations of the absorption and emission spectra of 1 were carried out with B3LYP method on the basis of the experimental structure.