Accessing S n≥2 States of a TADF Emitter by Femtosecond NIR Spectroscopy
Year: 2026
Type: article
Abstract: ABSTRACT A thermally activated delayed fluorescence (TADF) emitter consisting of a triarylamine (TAA) donor and a 1,4‐dicyanobenzene (DCN) acceptor moiety was characterized by femtosecond UV‐Vis and near infrared (NIR) spectroscopy. The combination of the two techniques allows to probe spectral changes of the emitter in a range extending from 350 to 1600 nm. With the approach, low‐lying higher singlet excitations (S n≥2 ) contributing to intersystem crossing via spin vibronic mechanisms can be located energetically. Due to the charge transfer (CT) character of the S 1 state, the transition energies S 1 →S n≥2 are strongly solvent dependent as experiments on TAA‐DCN dissolved in cyclohexane, toluene, 1,2‐dimethoxyethane, and acetonitrile indicate. The experiments also hold information on dielectric and vibrational relaxation ensuing S 1 excitation.
Source: Chemistry - A European Journal
DOI: 10.1002/chem.70875
Institutions: Heinrich Heine University Düsseldorf, TU Dortmund University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,640
Funder: Deutsche Forschungsgemeinschaft
OpenAlex ID: W7140143338