Synthesis, characterization, photophysical and electrochemical properties of fac-tricarbonyl(4,7-dichloro-1,10-phenanthroline)rhenium(I) complexes

Synthesis, crystal structure and electroluminescent properties of fac-bromotricarbonyl ([1,2,5]oxadiazolo[3',4':5,6]pyrazino- [2,3-f][1,10]phenanthroline) rhenium (I)

“…Characteristic lifetime of the excited state in the solution at 300 K was 186 ns (  15%) and absolute quantum yield was 0.016  0.003. These data were in good agreement with values reported previously for other Re(I) diimine complexes with predomination of 3 MLCT phosphorescence. A very specific property of phosphors based on heavy d-elements, and among them for rhenium complexes, is their tendency to self-quenching or concentration quenching.…”

“…The observed quenching of luminescence in the solid state can be the consequence of the above mentioned intermolecular contacts. The emission and excitation spectra for the 8*10 Upon short wavelength excitation (360 nm) a strong emission of ligand at 412 nm has been observed along with weak phosphorescence of 3 MLCT state at 640 nm. One can assume from the analysis of excitation spectrum, that effective pumping of 3 MLCT state was achieved by radiation with wavelength around 478 nm.…”

“…The emission and excitation spectra for the 8*10 Upon short wavelength excitation (360 nm) a strong emission of ligand at 412 nm has been observed along with weak phosphorescence of 3 MLCT state at 640 nm. One can assume from the analysis of excitation spectrum, that effective pumping of 3 MLCT state was achieved by radiation with wavelength around 478 nm. This wavelength was matching maximum in absorption spectrum which was assigned to  3 MLCT transition.…”

“…This wavelength was matching maximum in absorption spectrum which was assigned to  3 MLCT transition. Indeed, if 485 nm excitation radiation has been used, the intensity of 3 MLCT luminescence increased dramatically. This observation has confirmed correctness of ascription of absorption band around 478 nm to  3 MLCT transition.…”

“…[1][2] Among all, complexes of Ir(III), Pt(II), Ru(II) and Os(II) are the most popular materials for solar cells and OLED (Organic Light Emitting Diode) applications. 3 Electronic structure of Re(I) complexes is similar to those elements, but its coordination chemistry is much less explored. [4][5] Heavy atom assisted spin-orbit coupling effect, which is common for complexes of heavy d-elements, brings to mixing of triplet and singlet states in excited complex.…”