Effects of solvent systems on two silver coordination complexes: From discrete structure to 2D sheet

摘要

Two mixed-ligand silver(I) coordination complexes (CCs), [Ag_4(mpyz)(npt)_2·(H_2O)_2]_n (1) and [Ag_4(mpyz) (npt)_2]_n (2) were synthesized with reactions of methyl-pyrazine(mpyz) and 3-nitro-1,2-benzenedicarboxylic acid (H2npt) with silver nitrate in different solvent systems and were structurally characterized by single-crystal X-ray crystallography. Structural differences of CCs are due to the effects of solvent systems and the intricacy of the self-assembly process for these systems. For 1, the Ag_4 unit which is like Y letter which stand upside and down and repeat to form a 1D-6~3-silver-ring which shares Ag1 and Ag2 only with npt ligands. The eight Ag ions of complex 2 are in a shape like the branches of a tree which repeat to form a 1D silver chain. Effects of solvents on the structures, as well as the intricacy of the self-assembly process were discussed. The photoluminescence, infrared spectroscopy (IR) and thermogravimetric analyses (TGA) behaviors of the compounds were also discussed.