New mononuclear oxalate complexes of copper(II) with 2D and 3D architectures: Synthesis, crystal structures and spectroscopic characterization

Two new mononuclear copper(II) species, [Cu(bpy)(C2O4)(H2O)]·H2O and [Cu(bpy)(C2O4)(H2O)]·H2C2O4, were obtained from an (oxalato)tantalate(V) solution in the presence of [Cu(bpy)2]2+. The compounds were characterized by IR, UV-vis and EPR spectroscopy and single-crystal X-ray diffraction analysis. Weak interactions in both compounds have a great impact on the overall crystal-structure architectures.