Solvent-dependent structural diversity of cadmium(II) coordination polymers: syntheses, characterizations, and luminescence properties

By changing the solvent, three cadmium(II) coordination polymers (CPs), [Cd(NH2-BDC)(DMA)(H2O)]n (1), {[Cd(NH2-BDC)2(DMF)2]·H2O}n (2) and {[(Me2NH2)2Cd2(NH2-BDC)3(H2O)]·DMF·8H2O}n (3), have been synthesized based on the V-shaped linker 5-aminoisophthalic acid and Cd(NO3)2·4H2O under the same reaction temperature (140 °C) (NH2-BDC = 5-aminoisophthalate, DMA = N,N-dimethylacetamide, DMF = N,N-dimethylformamide). Compound 1 features a 1-D ladder-like infinite chain. Compound 2 is a 2-D (4,4) net when the dinuclear [Cd2(COO)4O4] is regarded as a quadruply-connected node. Compound 3 shows a 2-D hamburger-like structure. Luminescent properties of 1–3 were detected at room temperature under the same excitation and emission wavelengths of 200–600 nm with the same interval of 5 nm. Moreover, the calculation of lattice constants and volumes, and density of states of CPs 1 and 2 were carried out to get better insight into the nature of the structure and luminescence.