Synthesis and structural characterization of lanthanide oxalate-oxydiacetate mixed-ligand coordination polymers {[Ln(oda)(H2O)x]2(ox)}n (x=3 for Ln = La, Ce, Pr, Gd, Tb and x=2 for Ln = Er)

Reactions of oxydiacetic acid (H2oda) with lanthanide oxide, nitrate, chloride, and carbonate gave six lanthanide oxalate-oxydiacetate mixed-ligand coordination polymers {[Ln(oda)(H2O)x]2(ox)}n [x = 3 for Ln = La, Ce, Pr, Gd, Tb, (1-5), and x = 2 for Ln = Er (6)]. Oxydiacetic acid is decomposed into oxalic acid in this reaction. In the crystal structures of 1-6, oxydiacetate and the lanthanides build a chain, and the oxalate groups bridge two chains to form 1-D double-chain ladder-shaped structures, connected by intermolecular hydrogen bonds to form a 2-D network structure. These compounds contain approximately 3.0 6.4 2 channels along the c-axis. The infrared spectra and thermal behaviors of 1-6 are also investigated.