A highly luminescent Eu(iii) complex based on an electronically isolated aromatic ring system with ultralong lifetime. Issue 21 (17th May 2018) - Kitagawa, Yuichi
Abstract : A Eu(iii ) complex with a large electronically isolated aromatic ring system induces a brilliant luminescence. Abstract : A luminescent Eu(iii ) complex with a large electronically isolated aromatic ring system, Eu(hfa)3 (DPPTO)2 (where hfa denotes hexafluoroacetylacetonate and DPPTO denotes 2-diphenylphosphoryltriphenylene), is reported. The light-harvesting efficiency of the Eu(iii ) complex was assessed from electronic absorption spectra. Luminescence properties were evaluated from luminescence spectra, excitation spectra, luminescence quantum yields, and luminescence lifetimes. A remarkably brilliant luminescence was observed because of the strong light absorption and the high luminescence quantum yield of the Eu(iii ) complex. Density functional theory calculations indicated an electronic separation between the energy-donating large π-conjugated orbital and the energy-accepting Eu(iii ) orbital. These findings demonstrate that novel Eu(iii ) photophysics can be induced by large electronically isolated aromatic ring systems.