Eu(dbm)3(Phen) - tris(dibenzoylmethane)phenanthroline europium(III) - is a typical tenary Eu3+complex with a ligand 1,3- diphenylpropane-1,3-dione and a secondary phenanthroline ligand coordinating to the europium core. Eu(dbm)3(Phen) displays red-orange phosphorescence emission at 615 nm with a narrow bandwidth (color purity) FWHM smaller than 100 cm-1 in OLEDs. Eu(dbm)3(Phen) is preferably co-deposited with a charge transport material to reduce the chance of self-quenching (concentration quenching) and to improve charge carrier mobilities.