Role of electronic localization in the phosphorescence of iridium sensitizing dyes

Abstract

In this work we present a systematic study of three representative iridium dyes, namely, Ir(ppy)3, FIrpic and PQIr, which are commonly used as sensitizers in organic optoelectronic devices. We show that electronic correlations play a crucial role in determining the excited-state energies in these systems, due to localization of electrons on Ir d orbitals. Electronic localization is captured by employing hybrid functionals within time-dependent density-functional theory (TDDFT) and with Hubbard-model corrections within the delta-SCF approach. The performance of both methods are studied comparatively and shown to be in good agreement with experiment. The Hubbard-corrected functionals provide further insight into the localization of electrons and on the charge-transfer character of excited-states. The gained insight allows us to comment on envisioned functionalization strategies to improve the performance of these systems. Complementary discussions on the delta-SCF method are also presented in order to fill some of the gaps in the literature.

15 pages, 14 figures

References in corpus (5)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• First principles study of electronic and structural properties of CuO
• Non-adiabatic Effects in the Dissociation of Oxygen Molecules at the Al(111) Surface
• Assessing computationally efficient isomerization dynamics: Delta-SCF density-functional theory study of azobenzene molecular switching
• Electronic correlations in organometallic complexes

Cited by in corpus (11)

• Hubbard-corrected DFT energy functionals: the LDA+U description of correlated systems
• Variational density functional calculations of excited states via direct optimization
• Anisotropy enhanced X-ray scattering from solvated transition metal complexes
• Excited-state potential-energy surfaces of metal-adsorbed organic molecules from Linear Expansion Δ-Self-Consistent Field Density-Functional Theory (ΔSCF-DFT)
• Donor and acceptor levels of organic photovoltaic compounds from first principles
• Orbital-optimized versus time-dependent density functional calculations of intramolecular charge transfer excited states
• TDDFT+$U$: Hubbard corrected approximate density-functional theory in the excited-state regime
• Unraveling the degradation mechanism of FIrpic based blue OLEDs: I. A theoretical investigation
• Ab Initio Many-Body Perturbation Theory Calculations of the Electronic and Optical Properties of Cyclometalated Ir(III) Complexes
• Decoherence and vibrational energy relaxation of the electronically excited PtPOP complex in solution
• Radical cation-induced exciton quenching and efficiency roll-off in blue phosphorescent organic light-emitting diodes