Structural and photophysical studies of europium complexes containing triazole ligands

Mono- and bistriazoles ligands have been used to prepare ternary mixed ligand europium(III) complexes in which the remaining ligands are dibenzoylmethane anions (DBM). The complexes were characterized by various measurements including single-crystal X-ray crystallography. Photophysical studies on both ligands and the complexes were carried out. The complexes show strong sharp red emissions in the solid state corresponding to 5D0 → 7FJ (J = 0–3) with a 5D0 → 7F2 (612–613 nm) transition as the most prominent one. It was shown that high thermal stability, luminescence intensity and quantum yield comparable or higher than those for the Eu(DBM)3Phen makes such complexes a promising material for OLED.