The investigation on first Co(III) pyridine-including half-salamo-like complexes

Abstract

Two structurally novel Co(III) complexes have been successfully constructed from the pyridine-including half-salamo-like ligands (HL1 and HL2), namely as [Co(L1)(N3)2] (1) and [Co(L2)(N3)2] (2). The structural features of complexes 1 and 2 have been confirmed by means of single crystal X-ray diffraction experiment. The structural studies revealed that complexes 1 and 2 have similar structures. The characterization of the two ligands and their Co(III) complexes was ascertained by means of infrared spectra, ultraviolet spectra and Hirshfeld surfaces analyses. In addition, compared with the ligands HL1 and HL2, the fluorescence intensities of the corresponding complexes 1 and 2 decreased significantly. When Co(II) salt was gradually added to the ligand solution, the intensity of the fluorescence emission peak decreased with the continuous addition of Co(II) salt until this trend stopped, which indicates that the introduction of Co(II) ion leads to the charge transfer from the ligand to Co(III) ion.