Frontispiece: Detection of the Dark States in Thermally Activated Delayed Fluorescence (TADF) Process of Electron Donor‐Acceptor Dyads: Insights from Optical Transient Absorption Spectroscopy

Unraveling the complicated photophysics of thermally activated delayed fluorescence (TADF) compounds is not a trivial task, although it is critical to improve the performance of TADF emitters in OLED. In the Review by Zhao and colleagues (DOI: 10.1002/chem.202203737), recent developments of using the transient optical spectroscopic methods to study the photophysics of TADF emitters are summarized, e. g. the manifestation of the theoretically proposed spin-vibronic coupling effect and the three-state model describing the reverse intersystem crossing (RISC) in time-resolved transient absorption spectra.