Near-UV to red-emitting charged bis-cyclometallated iridium(iii) complexes for light-emitting electrochemical cells
- 21 October 2011
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Dalton Transactions
- Vol. 41 (1), 180-191
- https://doi.org/10.1039/c1dt10698h
Abstract
Herein we report a series of charged iridium complexes emitting from near-UV to red using carbene-based N⁁C: ancillary ligands. Synthesis, photophysical and electrochemical properties of this series are described in detail together with X-ray crystal structures. Density Functional Theory calculations show that the emission originates from the cyclometallated main ligand, in contrast to commonly designed charged complexes using bidentate N⁁N ancillary ligands, where the emission originates from the ancillary N⁁N ligand. The radiative process of this series of compounds is characterized by relatively low photoluminescence quantum yields in solution that is ascribed to non-radiative deactivation of the excited state by thermally accessible metal-centered states. Despite the poor photophysical properties of this series of complexes in solution, electroluminescent emission from the bluish-green to orange region of the visible spectrum is obtained when they are used as active compounds in light-emitting electrochemical cells.Keywords
This publication has 62 references indexed in Scilit:
- Ionic Iridium(III) Complexes with Bulky Side Groups for Use in Light Emitting Cells: Reduction of Concentration QuenchingAdvanced Functional Materials, 2009
- A Supramolecularly-Caged Ionic Iridium(III) Complex Yielding Bright and Very Stable Solid-State Light-Emitting Electrochemical CellsJournal of the American Chemical Society, 2008
- Blue‐Emitting Cationic Iridium Complexes with 2‐(1H‐Pyrazol‐1‐yl)pyridine as the Ancillary Ligand for Efficient Light‐Emitting Electrochemical CellsAdvanced Functional Materials, 2008
- A short history of SHELXActa Crystallographica Section A Foundations of Crystallography, 2007
- Origin of the large spectral shift in electroluminescence in a blue light emitting cationic iridium(iii) complexJournal of Materials Chemistry, 2007
- Improved Turn-on Times of Iridium Electroluminescent Devices by Use of Ionic LiquidsChemistry of Materials, 2005
- Molecular excitation energies to high-lying bound states from time-dependent density-functional response theory: Characterization and correction of the time-dependent local density approximation ionization thresholdThe Journal of Chemical Physics, 1998
- An empirical correction for absorption anisotropyActa Crystallographica Section A Foundations of Crystallography, 1995
- Ab initio effective core potentials for molecular calculations. Potentials for K to Au including the outermost core orbitalsThe Journal of Chemical Physics, 1985
- Relationship between Absorption Intensity and Fluorescence Lifetime of MoleculesThe Journal of Chemical Physics, 1962