An investigation of two heterobimetallic [Cu(II)2Ln(III)] (Ln = La and Ce) complexes of a more flexible bis(salamo)‐type ligand

Abstract

Two heterobimetallic [Cu(II)2Ln(III)] (Ln = La and Ce) complexes composed of flexible bis(salamo)‐type ligand H4L with Cu(II) and Ln(III) atoms, [Cu2La(L)(ƞ2-NO3)3]·EtOH (1) and [Cu2Ce(L)(ƞ2-NO3)3]·EtOH (2) have been successfully synthesized, and characterized by IR spectra, elemental analyses, UV–Vis spectroscopy, the crystal structures of the complexes 1 and 2 were determined by single-crystal X-ray diffraction analyses. Each Cu(II) atom of the complexes 1 and 2 is located in the N2O2-donor of the completely deprotonated (L)4− unit, so that the two Cu(II) atoms have tetra-coordinated slightly distorted square planar geometries, while the Ln(III) (La or Ce) atom is located in the O5 cavity of the ligand (L)4− unit. At the same time, there are six oxygen atoms from three bidentate nitrate groups coordinated with the Ln(III) (La or Ce) atom, resulting in the formation of an eleven-coordinated augmented sphenocorona J87. In addition, DFT calculations and Hirshfeld surfaces analyses are performed and fluorescence properties are evaluated.