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Iridium(III) Complexes with Orthometalated Phenylimidazole Ligands Subtle Turning of Emission to the Saturated Green Colour

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Abstract

A series of novel six iridium complexes (1–6) bearing two substituted phenylimidazole and an additional acetylacetone as the third co-auxilary ligand are reported. The lowest absorption band for all iridium complexes consist of a mixture of heavy atom Ir(III) enhanced 3MLCT and 3 π-π* transitions and the phosphorescent peak wavelength can be fine-tuned to cover the spectral range 455–518 nm with high quantum efficiencies. The peak wavelength of the dopants can be finely tuned depending upon the electronic properties of the substituents. On the basis of onset potentials of the oxidation and reduction, the HOMO-LUMO energies were calculated and the reported iridium complexes emit green light with exceeding higher efficiency.

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Acknowledgements

One of the authors Dr. J. Jayabharathi, Reader in Chemistry, Annamalai University is thankful to Department of Science and Technology [No. SR/S1/IC-07/2007], University Grants Commission (F. No. 36-21/2008 (SR)) for providing fund to this research work and Prof. C.H. Cheng, Chairman, National Science Council, National Tsing Hua University for my post-doctoral research work.

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Authors and Affiliations

  1. Department of Chemistry, Annamalai University, Annamalainagar, 608002, Tamilnadu, India

    Jayaraman Jayabharathi, Venugopal Thanikachalam, Kanagarathinam Saravanan & Natesan Srinivasan

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  1. Jayaraman Jayabharathi
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  2. Venugopal Thanikachalam
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  3. Kanagarathinam Saravanan
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  4. Natesan Srinivasan
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Correspondence to Jayaraman Jayabharathi.

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Jayabharathi, J., Thanikachalam, V., Saravanan, K. et al. Iridium(III) Complexes with Orthometalated Phenylimidazole Ligands Subtle Turning of Emission to the Saturated Green Colour. J Fluoresc 21, 507–519 (2011). https://doi.org/10.1007/s10895-010-0737-7

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