Syntheses, Structures and Photoluminescence of Two New Layered Lanthanide Coordination Polymers with Thiophenedicarboxylic Acid and 1,10-Phenanthroline

Two isostructural layered coordination polymers constructed from mixed ligands, [Ln2(tdc)3(phen)2(H2O)2] (Ln = Sm 1, Eu 2, H2tdc = thiophene-2,5-dicarboxylic acid, phen = 1,10-phenanthroline), have been hydrothermally synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Crystal data for 1: triclinic, space group P1 with a = 10.546(2), b = 11.201(2), c = 18.644(4) , α = 106.69(3), β = 91.27(3), γ = 94.43(3)°, Dc = 1.909 g·cm-3, F(000) = 1180, μ = 2.992 mm-1, Z = 2, the final R = 0.0300 and wR = 0.0656 for 6968 observed reflections with I > 2σ(I). And those for 2: triclinic, space group P1 with a = 10.557(2), b = 11.159(2), c = 18.588(2) , α = 106.945(6), β = 91.255(6), γ = 94.359(6)°, Dc = 1.927 g·cm-3, F(000) = 1184, μ = 3.204 mm-1, Z = 2, the final R = 0.0221 and wR = 0.0459 for 6328 observed reflections with I > 2σ(I). The title complexes show a two-dimensional (2D) square grid structure constructed from paddle-wheel-like [Ln2(CO2)4] dimers and tdc ligands. The 2D layers were further assembled into a 3D supramolecular assembly via O–H···O hydrogen bond. The photoluminescence properties of complexes 1 and 2 were investigated.