Luminescent and Magnetic Properties of Lanthanide-Thiophene-2,5-dicarboxylate Hybrid Materials

Three lanthanide-thiophenedicarboxylate hybrid compounds, [(Eu-2(TDC)(3)(CH3OH)(2)center dot(CH3OH)] (1), [(Yb-2(TDC)(3)(DMF)(H2O)center dot(CH3CH2OH)] (2), and [(Tb-2(TDC)(3)(H2O)(4)] (3) (where TDC is deprotonated thiophene-2,5-dicarboxylic acid and DMF is dimethylformamide), have been prepared by a hydrothermal method. The TDC ligands exhibit two unprecedented (kappa(2)-kappa(1)-mu(2))-(kappa(1)-kappa(1))-mu(5) and (kappa(2))-(kappa(2))-mu(2) coordination modes as well as other various modes. Structure analysis reveals that 2,5-thiophenedicarboxylic acid play a versatile role toward different lanthanide ions to form three-dimensional inorganic-organic hybrid frameworks. The luminescence experiments show that Eu(III) and Tb(III) compounds exhibit typical luminescence in the visible region, while the Yb(III) compound emits characteristic near-infrared luminescence in the solid state even with the coordinated water molecules. Besides luminescence, the Tb(III) compound also shows weak ferromagnetic behavior, which indicates that it is acting as a dual function material