Theoretical Study of Phosphorescence of Iridium Complexes with Fluorine‐Substituted Phenylpyridine Ligands

Abstract

Time-dependent density functional theory (TD-DFT) with linear and quadratic response approaches was applied to calculate absorption and luminescence spectra of a number of facial and meridional iridium complexes with fluorine-substituted phenylpyridine (F n ppy) ligands. The absorption and luminescence spectra were studied to simulate the photophysical properties of electroluminescent devices fabricated on the basis of these iridium complexes used to increase spin-orbit coupling and the triplet-state blue emission of the corre-

Organometallic Materials for Electroluminescent and Photovoltaic Devices

“…Substitution of ligands can influence HOMO and LUMO energies and their mixing with metal 5d-AOs, thus modulating the phosphorescence lifetime and tuning of its wavelength. A series of TD DFT calculations with SOC treatment by quadratic response provide a very good explanation of emission tuning in various CIC www.intechopen.com compounds and illustrate the physical reasons for OLED architecture and design (Li et al, 2011, Minaev et al, 2009, Janson et al, 2007, Nozaki 2007). …”

“…Some variations in φ p are explained by SOC calculations of the G 1,0 coefficient, Eq. (15) (Li et al 2011). Analysis of Eq.…”

“…In the TD DFT study carried out by Li et al (2011), linear and quadratic response approaches are employed to investigate the absorption and luminescence spectra of several facial and www.intechopen.com meridional iridium complexes with fluorine-substituted phenylpyridine (F n ppy) ligands, as shown in Fig. 3.…”

Chemical Tuning and Absorption Properties of Iridium Photosensitizers for Photocatalytic Applications

“…It should be noted that the nature of the lowest-lying triplet states is of primary importance for light-emitting devices and photocatalytic reactions. However, the main focus in this communication is put on the absorption properties, where the properties of singlet states are of primary interest [40][41][42].…”

“…However, the intensities of the spin-forbidden singlet-triplet transitions were not calculated, although Ir has large spin-orbit coupling constant. Recently, it was shown that singlet/triplet mixing in similar Ir photosensitizers has only a minor impact on the absorption spectra and results in small red shifts of the bands in the visible range and a decrease of intensities as triplet states possess small oscillator strengths [40][41][42]. As we have not aimed at fitting spectral widths for various PSs and transitions of different nature, a Gaussian broadening with a universal parameter (0.25 eV) has been applied to all stick-spectra.…”