Synthesis, Crystal Structure, and Photophysical Properties of Heteroleptic Ruthenium(II) Complexes with Functionalized Diimine Ligands

Four carbonyl hydrido RuII complexes with different functionalized α,α'-diimine ligands have been synthesized and well characterized by IR, UV/vis, CV, ESI/MS, and 1H NMR spectra. One of the complexes was also characterized by X-ray crystallography. The luminescence of these complexes has been investigated at room temperature in CH2Cl2 solution and low temperature glassy media at 77 K. The emissions are originated from either ligand-centered π–π* transitions or metal center to ligand charge transfer (MLCT), which are highly dependent on the properties of the α-diimine ligands.