Four rare structurally characterized hetero-pentanuclear [Zn(4)Ln] bis(salamo)-type complexes: syntheses, crystal structures and spectroscopic properties

Four new hetero-pentanuclear 3d–4f complexes [Zn(4)(L)(2)La(NO(3))(2)(OEt)(H(2)O)] (1), [Zn(4)(L)(2)Ce(NO(3))(2)(OMe)(MeOH)] (2), [Zn(4)(L)(2)Pr(NO(3))(2)(OEt)(EtOH)] (3) and [Zn(4)(L)(2)Nd(NO(3))(2)(OMe)(MeOH)] (4) were synthesized by the reactions of a newly synthesized octadentate bis(salamo)-based tetraoxime ligand (H(4)L) with Zn(OAc)(2)·2H(2)O and Ln(NO(3))(3)·6H(2)O (Ln = La, Ce, Pr and Nd), respectively, and characterized via elemental analyses, FT-IR, UV-Vis spectroscopy and single crystal X-ray crystallography. The X-ray crystallographic investigation revealed that all Zn(II) ions were located in N(2)O(3) coordination spheres, and possessed a trigonal bipyramid coordination environment. The Ln(III) ion lay in an O(8) coordination sphere, and adopted a distorted square antiprismatic coordination environment. Furthermore, supramolecular interactions and fluorescence properties were investigated.