Intramolecular Noncovalent Interactions Facilitate Thermally Activated Delayed Fluorescence (TADF)

Xian Kai Chen, Brandon W. Bakr, Morgan Auffray, Youichi Tsuchiya, C. David Sherrill, Chihaya Adachi, Jean Luc Bredas

Research output: Contribution to journalArticlepeer-review

63 Citations (Scopus)


In the conventional molecular design of thermally activated delayed fluorescence (TADF) organic emitters, simultaneously achieving a fast rate of reverse intersystem crossing (RISC) from the triplet to the singlet manifold and a fast rate of radiative decay is a challenging task. A number of recent experimental data, however, point to TADF emitters with intramolecular π-πinteractions as a potential pathway to overcome the issue. Here, we report a comprehensive investigation of TADF emitters with intramolecular π···πor lone-pair···πnoncovalent interactions. We uncover the impact of those intramolecular noncovalent interactions on the TADF properties. In particular, we find that folded geometries in TADF molecules can trigger lone-pair···πinteractions, introduce a n → π∗ character of the relevant transitions, enhance the singlet-triplet spin-orbit coupling, and ultimately greatly facilitate the RISC process. This work provides a robust foundation for the molecular design of a novel class of highly efficient TADF emitters in which intramolecular noncovalent interactions play a critical function.

Original languageEnglish
Pages (from-to)3260-3268
Number of pages9
JournalJournal of Physical Chemistry Letters
Issue number12
Publication statusPublished - Jun 20 2019

All Science Journal Classification (ASJC) codes

  • General Materials Science
  • Physical and Theoretical Chemistry


Dive into the research topics of 'Intramolecular Noncovalent Interactions Facilitate Thermally Activated Delayed Fluorescence (TADF)'. Together they form a unique fingerprint.

Cite this