Two di-nuclear Cd(II) and Mn(II) complexes with one new poly-dentate double Schiff base ligand derived from 1,10-phenanthroline: Syntheses, structures, and physical properties

摘要

A new poly-dentate double Schiff base ligand 1,10-phenanthroline-2,9-dicarboxaldehyde-di-2-hydroxybenzoylhydrazone (H2L) was synthesized and structurally characterized. Two Cd-II and Mn-II dimers of this ligand were also synthesized, and their crystal structures and photoelectronic spectra were characterized. In the two dimers, ligand L acts as a bridge in the interesting mono poly-dentate bridging mode. The ligand and its Cd-II complex strongly emit at 525 nm and 570 nm, respectively, and thus can be utilized as potential fluorescent materials. Furthermore, magnetization measurements for its Mn-II dimer in the range 5-300 K indicate two magnetic orderings, at high temperature (T > 230 K) a ferromagnetic ordering is observed, and below this temperature, an antiferromagnetic behavior takes place.