Investigating into crystal structures and supramolecular architectures of four newly synthesized hetero-octanuclear [Cu4II-Ln4III] (Ln = Sm, Eu, Tb and Dy) complexes produced by a hexadentate bisoxime chelate ligand

Four unprecedented 3d-4f hetero-octanuclear family-type complexes [{Cu(L)Ln(NO3)(3)}(2)][Cu(L)Ln(NO3)(3)](2) (Ln = Sm (1), Eu (2), Tb (3) and Dy (4)) were synthesized by an unsymmetric single salamo-like ligand H2L (6-Methoxy-6 '-ethoxy-2,2 '-[ethylenedioxybis(nitrilomethylidyne)]diphenol) with Cu(OAc)(2)center dot H2O and Ln (NO3)(3)center dot 6H(2)O (Ln = Sm, Eu, Tb and Dy), respectively. X-ray crystallography revealed that each hetero-octa-nuclear 3d-4f metal complexes [{Cu(L)Ln(NO3)(3)}(2)][Cu(L)Ln(NO3)(3)](2) contains one neutral dimer [{Cu(L)Ln (NO3)(3)}(2)] unit and two independent [Cu(L)Ln(NO3)(3)] units. At the same time, the four Cu(II) atoms of the complexes 1-4 have four-and five-coordinated configurations, while the four Ln(III) atoms have only one configuration, all of which are ten-coordinated. The structures of the four complexes 1-4 were characterized via elemental analyses, PXRD, FT-IR and UV-Vis spectroscopy. In addition, while studying the crystal structure, the supramolecular interactions and spectral properties of the complexes 1-4 were studied in detail.