Influence of different counteranions on supramolecular self-assemblies, Hirshfeld surfaces analyses and fluorescence properties of three multi-nuclear Cu(II) salamo-based complexes

Abstract

Three new multi-nuclear Cu(II) complexes, [Cu4(L)2(CH3OH)2](NO3)2·2CH3OH (1), [Cu4(L)2(CH3OH)(CH3CN)](ClO4)2·2CH3OH (2) and [Cu4(HL)2(μ2-Cl)2Cl2(CH3CH2OH)2][CuCl2]·CHCl3 (3) have been successfully synthesized by the one-pot reaction of a bis(salamo)-based ligand H3L with Cu(NO3)2·3H2O, Cu(ClO4)2·6H2O and CuCl2·2H2O, respectively. Complexes 1 and 2 are monoclinic systems including four Cu(II) atoms with two completely deprotonated ligand (L)3- units, which form centrosymmetric helical molecules. Complex 3 is triclinic system including five Cu(II) atoms with two incompletely deprotonated ligand (HL)2- units, which forms an expanded structural molecule. Complexes 1–3 have been characterized by elemental analyses, IR, UV–Vis spectroscopy and single crystal X-ray crystallography. In addition, supramolecular interactions, Hirshfeld surfaces analyses, effects of counteranions and fluorescence properties were also investigated.