Syntheses and characterizations of two new pillared-layer coordination polymers constructed from lanthanides and mixed O-donor ligands

Two new pillared-layer frameworks have been obtained through self-assembly of 4,4′-azobenzene dicarboxylatic acid (4,4′-H2ABDC), oxalate, hydroxyl and LnCl3(Ln = Sm, Eu) under hydrothermal environment and characterized by TGA, IR spectroscopy, element analyses, and X-ray single crystal diffraction. The X-ray structure analyses reveal that the oxalates link the Ln(III) to form metal layers, and 4,4′-ABDC ligands work as pillars to connect adjacent layers to further extend into 3D frameworks. Their magnetic studies show that the two compounds have typical anti-ferromagnetic behaviors.