Premium
Influence of Linked Bridges on Thermally Activated Delayed Fluorescence Characteristic for DCBPy Emitter
Author(s) -
Gao Ying,
Yang XiaoDong,
Wu ShuiXing,
Geng Yun
Publication year - 2019
Publication title -
advanced theory and simulations
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.068
H-Index - 17
ISSN - 2513-0390
DOI - 10.1002/adts.201900076
Subject(s) - intersystem crossing , excited state , singlet state , fluorescence , atomic physics , radiative transfer , excitation , spin–orbit interaction , materials science , chemistry , molecular physics , physics , condensed matter physics , optics , quantum mechanics
In this work, four compounds ( 2–5 ) are designed based on reported DCBPy ( 1 ) to investigate the influence of linked bridges on thermally activated delayed fluorescence properties. The results indicate that 2–5 have stronger oscillator strength and higher fluorescence radiative rate ( k r ) after introducing linked bridges. But, the increased local‐excitation and decreased charge‐transfer natures in the lowest singlet and triplet excited states lead to larger singlet‐triplet energy splitting (Δ Ε ST ) for 2–5 than 1 . The potential reverse intersystem crossing (RISC) channels are speculated for 1–5 by considering the higher triplet excited state and spin‐orbit coupling (SOC) matrix element. It is concluded that the introduction of bridges noticeably enhances the SOC between singlet (S n ) and triplet (T n ) excited states. By analyzing the excited state energies and transition natures, 2 and 3 are expected to undergo a T 3 to S 1 RISC process, and 4 and 5 are expected to undergo a RISC more significantly via T 2 to S 1 because of the almost equal energy levels and strong SOC.