Related Experiment Video
Updated: May 31, 2025
Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera
Published on: December 27, 2018
Design Rule of Tetradentate Ligand-Based Pt(II) Complex for Efficient Singlet Exciton Harvesting in Fluorescent
Unhyeok Jo1, Kiun Cheong1, Jae-Min Kim2
1School of Chemical Engineering, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do 16419, Republic of Korea.
Abstract:
Controlling intermolecular interactions, such as triplet-triplet annihilation (TTA) and triplet-polaron annihilation (TPA), is crucial for achieving high quantum efficiency in organic light-emitting diodes (OLEDs) by suppressing exciton loss. This study investigates the molecular design of tetradentate Pt(II) complexes used for singlet exciton harvesting in fluorescent OLEDs to elucidate the relationship between the chemical structure of the ligands and exciton quenching mechanisms. It was discovered that the bulkiness of substituents is pivotal for maximizing quantum efficiency in these devices. An exciton dynamics study conducted during device operation quantitatively analyzed the contribution of substituents to the OLED operation mechanism, demonstrating that complexes with bulky 2,6-diisopropylphenyl and tert-butyl substituents enhance singlet exciton harvesting by suppressing TTA and TPA, thereby facilitating Förster energy transfer.
Related Concept Videos
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
02:51Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
01:26Variables Affecting Phosphorescence and Fluorescence
01:22EDTA: Chemistry and Properties
01:26Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...