Hydrothermal synthesis and crystal structures of two lanthanide coordination polymers with novel tetradentate-coordinated perchlorates

Two new 3D lanthanide coordination polymers {Ln(C₂O₄)(ClO₄)(H₂O)] · Cl}_n Ln = Pr (1) and Nd (2)] have been synthesized by hydrothermal reactions and characterized by elemental analysis, X-ray single-crystal analyses, IR and Raman spectroscopy. X-ray crystal structure analyses reveal that compounds 1 and 2 are isostructural and crystallized in the space group P2₁/c. A 1D zigzag chains formed by oxalate ligands in μ₂-mode to bridge Ln(III) atoms present in the two complexes and the adjacent zigzag chains were further connected by μ₃-η¹:η¹:η¹:η¹ fashion of into a 3D framework with ordered 1D channels, in which uncoordinated Cl⁻ anions are located as counterions. In addition, the IR and Raman spectrum further confirm the presence of tetradentate-coordinated perchlorates.