title: The influence of triplet energy levels of bridging ligands on energy transfer processes in Ir(III)/Eu(III) dyads.
abstract: A series of N^N,O^O-bridging ligands based on substituted 1-(pyridin-2-yl)-3-methyl-5-pyrazolone and their corresponding heteroleptic iridium(III) complexes as well as Ir-Eu bimetallic complexes were synthesized and fully characterized. The influence of the triplet energy levels of the bridging ligands on the energy transfer (ET) process from the Ir(III) complexes to Eu(III) ions in solution was investigated at 77 K in Ir(III)/Eu(III) dyads. Photophysical experiment results show the bridging ligands play an important role in the ET process. Only when the triplet energy level of the bridging ligand was lower than the triplet metal-to-ligand charge transfer ((3)MLCT) energy level of the Ir moiety, was pure emission from the Eu(III) ion observed, implying complete ET took place from the Ir moiety to the Eu(III) ion.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
authors.forename: Weili
authors.initials: W
authors.lastname: Jiang
authors.forename: Bin
authors.initials: B
authors.lastname: Lou
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Wang
authors.forename: Hongbin
authors.initials: H
authors.lastname: Lv
authors.forename: Zuqiang
authors.initials: Z
authors.lastname: Bian
authors.forename: Chunhui
authors.initials: C
authors.lastname: Huang
mesh_terms: D018360:Crystallography, X-Ray; D004735:Energy Transfer; D005063:Europium / Q000737:chemistry*; D007495:Iridium / Q000737:chemistry*; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D009942:Organometallic Compounds / Q000737:chemistry; D047069:Pyrazolones / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D047069:Pyrazolones; D007495:Iridium; D005063:Europium