In:
ChemPlusChem, Wiley, Vol. 78, No. 8 ( 2013-08), p. 852-859
Abstract:
The bridging ligands in d–f bimetallic complexes play an important role in the excitation energy transfer (EET) process. To elaborate on the effect of the ligand on the EET process, a series of bridging ligands (μ‐ L ), 1‐(1′,10′‐phenanthrolin‐2′‐yl)‐4,4,4‐trifluorobutane‐1,3‐dione (phen3f), 1‐(1′,10′‐phenanthrolin‐2′‐yl)‐4,4,5,5,5‐pentafluoropentane‐1,3‐dione (phen5f), 1‐(2,2′‐bipyridine‐6‐yl)‐4,4,4‐trifluorobutane‐1,3‐dione (bpy3f), and 1‐(2,2′‐bipyridine‐6‐yl)‐4,4,5,5,5‐pentafluoropentane‐1,3‐dione (bpy5f), and their corresponding iridium complexes, [(dfppy) 2 Ir(μ‐ L )] (dfppy=2‐(4′,6′‐difluorophenyl)pyridinato‐N,C2′), as well as their corresponding heteroleptic Ir III –Eu III complexes [{(dfppy) 2 Ir(μ‐L)} 3 EuCl]Cl 2 were synthesized and characterized. Photophysical and kinetic results revealed that the alternation of the bridge ligand resulted in a systemic difference in the lowest triplet‐state energy (T 1 ) of the iridium complexes, the EET efficiency from iridium complexes to the Eu III ion, and a significant difference in the total luminescence quantum yields. Based on the nanosecond time‐resolved phosphorescence spectra, a model for the energy‐transfer mechanism was proposed for d–f bimetallic complexes, which indicated that the nonradiative relaxation of the excited energy of Eu III , especially energy dissipation by means of the T 1 state, was the main reason for the discrepancy in the quantum yields of the four Ir III –Eu III complexes.
Type of Medium:
Online Resource
ISSN:
2192-6506
,
2192-6506
DOI:
10.1002/cplu.201300107
Language:
English
Publisher:
Wiley
Publication Date:
2013
detail.hit.zdb_id:
2646595-4
Permalink