Syntheses and characterizations of two novel Ln(III)–Cu(II) coordination polymers constructed by Pyridine-2,4-dicarboxylate ligand

Two novel three dimension Ln(III)–Cu(II) coordination polymers [Gd2Cu(pydc)4(H2O)6]n and [Sm2Cu3(pydc)6(H2O)6]n were prepared by the hydrothermal reactions of CuO, Ln2O3 (Ln = Gd, Sm), H2pydc (H2pydc = 2,4-pyridinedicarboxylic acid) and characterized by single-crystal X-ray diffraction analysis.