Synthesis, structure and luminescent properties of coordination polymers with 1,2-benzenedicarboxylic acid and a series of flexible dicarboxylate ligands

A series of lanthanide coordination polymers, namely, [Ln(ox)(0.5)(phth)(H2O)(2)]center dot 0.5H(2)O (Ln = Tb (1), Sm (2); H(2)ox = oxalic acid; H(2)phth = 1,2-benzenedicarboxylic acid), [Ln(mal)(0.5)(phth)(H2O)(2)]center dot H2O (Ln = Eu (3), Sm (4); H(2)mal = maleic acid), [Pr-3(mal')(phth)(3)(H2O)(3)]center dot H2O (5) (H(2)mal' = malic acid) [Eu(ad)(0.5)(phth)(H2O)(2)] (Ln = Eu (6), Sm (7); H(2)ad = adipic acid), [Pr-2(ad)(phth)(2)(H2O)(4)] (8) have been synthesized hydrothermally from the self-assembly of the lanthanide ions (Ln(3+)) with different types of flexible dicarboxylate ligands and the rigid 1,2-benzenedicarboxylate ligand. All coordination polymers were characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Structural analyses reveal that the networks of all eight complexes exhibit a variety of coordination modes at the metal centers. The thermal stabilities for 1, 3, 5, 6, 8, photoluminescent properties for 1-4 and 6-7 were examined, and the results show that the complexes seem to be good candidates for novel hybrid inorganic-organic photoactive materials with excellent thermal stability.