| In order to study on PL properties,severalβ-diketone with ICT function and corresponding Eu(Ⅲ),Ir(Ⅲ) complexes have been designed and synthesized. DBM,NBM and their Eu(Ⅲ),Ir(Ⅲ) complexes also been investigated to show contrast.Photophysical studies demonstrated that no energy was migrated from the ICT excited state of the ligands to Eu3+,and that Eu3+ was sensitized by the triplet state. The triplet state energy level of NDBM and NDP decrease as the incorporation of the dimethylamino moiety into DBM and NBM respectively,which cause the conjugation system is enlarged.We concluded that the incorporation of the dimethylamino moiety affect the ISC of CDBM and further impaired the whole sensitization process. Quantum yields of Eu(NDBM)3·3H2O and Eu(NDP)3·3H2O are less than Eu(DBM)3·2H2O and Eu(NBM)3·2H2O.The ICT fluorescence quantum yields of NDBM and NDP decrease after coordinating with Gd3+ and Eu3+.In solution,the emission intensity of Eu3+ in Eu(NDP)3Phen·H2O and Eu(NDBM)3Phen is still weak. There is no observable ligand emission in the solid state emission spectra in Eu(NDBM)3Phen,Eu(NDBM)3·3H2O and Eu(NDP)3·3H2O,ICT fluorescence have been quenched in the solid state.In order to investigate effect of ICT and energy levels of ancillary ligands on red phosphorescent Iridium(Ⅲ) complexes,we synthesize Ir(DBQ)2(LX)(LX=acac, DBM,NDBM,NBM,NDP).For all of the complexes discussed thus far,the triplet levels of the ligands lie above the energies of the C^N ligand and MLCT excited states.Thus,the luminescence is dominated by C^N and MLCT transitions.In degassed CH2Cl2 solution at room temperature,theλmax/nm(emmision) of Ir(DBQ)2(LX)(LX=DBM,NDBM,NBM,NDP) is about 620 nm.Phosphorescent quantum yields decrease as the triplet energy level differences between Ir(DBQ)2 andβ-diketone decrease.Strong spin-orbit coupling of the Ir(Ⅲ) leads to efficient intersystem crossing of the singlet excited states to the triplet manifold,so the ICT fluorescence quantum yields of ancillary ligands decrease drastically.The energy transfer from triplet excited states of ancillary ligands to triplet energy level of Ir(DBQ)2.
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