Interligand energy transfer in europium(III) mesogenic adducts

An analysis of the absorption and luminescence spectra and luminescence kinetics showed that in the Eu(DK)₃bpy_17-17 mesogenic adduct, 5,5′-diheptadecyl-2,2′-bipyridine (bpy_17-17) took an active part in the energy transfer to the Eu³⁺ ion. The interligand energy transfer from β-diketonate (DK) ligands was the major mechanism of excitation of bpy_17-17. Importantly, the interligand excitation complex considerably decreased radiation losses during the energy transfer from the absorbing DK ligands to the emitting level of Eu³⁺.