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Title: Phosphorescence lifetimes of organic light-emitting diodes from two-component time-dependent density functional theory

Abstract

“Spin-forbidden” transitions are calculated for an eight-membered set of iridium-containing candidate molecules for organic light-emitting diodes (OLEDs) using two-component time-dependent density functional theory. Phosphorescence lifetimes (obtained from averaging over relevant excitations) are compared to experimental data. Assessment of parameters like non-distorted and distorted geometric structures, density functionals, relativistic Hamiltonians, and basis sets was done by a thorough study for Ir(ppy){sub 3} focussing not only on averaged phosphorescence lifetimes, but also on the agreement of the triplet substate structure with experimental data. The most favorable methods were applied to an eight-membered test set of OLED candidate molecules; Boltzmann-averaged phosphorescence lifetimes were investigated concerning the convergence with the number of excited states and the changes when including solvent effects. Finally, a simple model for sorting out molecules with long averaged phosphorescence lifetimes is developed by visual inspection of computationally easily achievable one-component frontier orbitals.

Authors:
 [1];  [1]
  1. Institut für Physikalische Chemie, Karlsruher Institut für Technologie, Kaiserstraße 12, 76131 Karlsruhe (Germany)
Publication Date:
OSTI Identifier:
22413297
Resource Type:
Journal Article
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 141; Journal Issue: 22; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9606
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CONVERGENCE; DENSITY FUNCTIONAL METHOD; EXCITATION; EXCITED STATES; HAMILTONIANS; INSPECTION; IRIDIUM; LIGHT EMITTING DIODES; MOLECULES; PHOSPHORESCENCE; RELATIVISTIC RANGE; SOLVENTS; SPIN; TIME DEPENDENCE

Citation Formats

Kühn, Michael, Weigend, Florian, and Institut für Nanotechnologie, Karlsruher Institut für Technologie, Postfach 3640, 76021 Karlsruhe. Phosphorescence lifetimes of organic light-emitting diodes from two-component time-dependent density functional theory. United States: N. p., 2014. Web. doi:10.1063/1.4902013.
Kühn, Michael, Weigend, Florian, & Institut für Nanotechnologie, Karlsruher Institut für Technologie, Postfach 3640, 76021 Karlsruhe. Phosphorescence lifetimes of organic light-emitting diodes from two-component time-dependent density functional theory. United States. https://doi.org/10.1063/1.4902013
Kühn, Michael, Weigend, Florian, and Institut für Nanotechnologie, Karlsruher Institut für Technologie, Postfach 3640, 76021 Karlsruhe. 2014. "Phosphorescence lifetimes of organic light-emitting diodes from two-component time-dependent density functional theory". United States. https://doi.org/10.1063/1.4902013.
@article{osti_22413297,
title = {Phosphorescence lifetimes of organic light-emitting diodes from two-component time-dependent density functional theory},
author = {Kühn, Michael and Weigend, Florian and Institut für Nanotechnologie, Karlsruher Institut für Technologie, Postfach 3640, 76021 Karlsruhe},
abstractNote = {“Spin-forbidden” transitions are calculated for an eight-membered set of iridium-containing candidate molecules for organic light-emitting diodes (OLEDs) using two-component time-dependent density functional theory. Phosphorescence lifetimes (obtained from averaging over relevant excitations) are compared to experimental data. Assessment of parameters like non-distorted and distorted geometric structures, density functionals, relativistic Hamiltonians, and basis sets was done by a thorough study for Ir(ppy){sub 3} focussing not only on averaged phosphorescence lifetimes, but also on the agreement of the triplet substate structure with experimental data. The most favorable methods were applied to an eight-membered test set of OLED candidate molecules; Boltzmann-averaged phosphorescence lifetimes were investigated concerning the convergence with the number of excited states and the changes when including solvent effects. Finally, a simple model for sorting out molecules with long averaged phosphorescence lifetimes is developed by visual inspection of computationally easily achievable one-component frontier orbitals.},
doi = {10.1063/1.4902013},
url = {https://www.osti.gov/biblio/22413297}, journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 22,
volume = 141,
place = {United States},
year = {2014},
month = {12}
}