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

Three lanthanide-thiophenedicarboxylate hybrid compounds, [(Eu 2 (TDC) 3 (CH 3 OH) 2 ·(CH 3 OH)] ( 1 ), [(Yb 2 (TDC) 3 (DMF)(H 2 O)·(CH 3 CH 2 OH)] ( 2 ), and [(Tb 2 (TDC) 3 (H 2 O) 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 (κ 2 -κ 1 -μ 2 )−(κ 1 -κ 1 )−μ 5 and (κ 2 )−(κ 2 )−μ 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.