Thermally activated delayed fluorescence (TADF) materials are commonly used in various apparatus, including organic light-emitting device-based displays, as they remarkably improve the internal quantum efficiencies. Although there is a wide range of donor–acceptor-based compounds possessing TADF properties, in this computational study, we investigated TADF and some non-TADF chromophores, containing benzophenone or its structural derivatives as the acceptor core, together with various donor moieties. Following the computational modeling of the emitters, several excited state properties, such as the absorption spectra, singlet–triplet energy gaps (Δ E ST ), natural transition orbitals, and the topological Φ S indices, have been computed. Along with the donor–acceptor torsion angles and spin-orbit coupling values, these descriptors have been utilized to investigate potential TADF efficiency. Our study has shown that on the one hand, our photophysical/structural descriptors and computational methodologies predict the experimental results quite well, and on the other hand, our extensive benchmark can be useful to pinpoint the most promising functionals and descriptors for the study of benzophenone-based TADF emitters.

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The thermally activated delayed fluorescence (TADF) behaviours of seventeen organic TADF emitters and two non-TADF chromophores bearing various donor and acceptor moieties were investigated, focusing on their torsion angles, singlet-triplet...

Thermally activated delayed fluorescence (TADF) materials are commonly used in various apparatus, including organic light emitting device (OLED)-based displays, as they remarkably improve the internal quantum efficiencies (IQE). Alt-hough there is a wide range of donor-acceptor based compounds possessing TADF properties, in this computational study we investigated TADF and some non-TADF chromophores, containing benzophenone or its structural derivatives as the acceptor core, together with various donor moieties. Following the computational modeling of the emitters, several excited state properties, such as the absorption spectra, singlet-triplet energy gaps (∆EST), natural transition orbitals (NTO) and the topological ΦS indices, have been computed. Along with the donor-acceptor torsion angles and spin-orbit coupling (SOC) values, these descriptors have been utilized to investigate potential TADF efficiency. Our study has shown that on the one hand, our photophysical/structural descriptors and computational methodologies predict the experi-mental results quite well, on the other hand, our extensive benchmark can be useful to pinpoint the most promising func-tionals and descriptors for the study of benzophenone based TADF emitters.

The thermally activated delayed fluorescence (TADF) behaviours of seventeen organic TADF emitters and two non-TADF chromophores bearing various donor and acceptor moieties were investigated, focusing on their torsion angles, singlet-triplet gap (ΔEST), spin orbit couplings (SOC) and topological ΦS index. Electronic structure calculations were performed in the framework of the Tamm-Dancoff approximation (TDA) allowing to characterize reverse intersystem crossing (RISC) probability between the S1 and T1 states. In addition, experimental ΔEST data were taken into account to choose the most appropriate functional and basis set, while absorption spectra were obtained by considering vibrational and dynamical effects through a Wigner sampling of the ground state equilibrium regions. Examining all the parameters obtained in our computational study, we rationalized the influence of electron-donating and electron-accepting groups and the effects of geometrical factors, namely torsion angles, on a wide class of diverse compounds ultimately providing an easy and computationally effective protocol to assess TADF efficiencies.

Stilbenes substituted with –CN, –OMe and –Br were synthesized using four different Lewis acid catalysts and their reaction efficiencies were compared. In addition to McMurry reagents known in literature, a more familiar and economical catalyst ZnCl2 was used for the first time in our reaction procedures. Furthermore, bromine substituted stilbenes were subjected to Suzuki coupling reactions to append a triphenylamine (TPA) unit, which enhances fluorescence emissions. Solvatochromic properties of synthesized stilbenes were investigated and aggregation caused quenching (ACQ) properties of TPA containing molecules were systematically examined. Optical properties were also theoretically investigated.

In this work, Thermally Activated Delayed Fluorescence (TADF) of a series of emitters with sulfone-based acceptor moieties were studied by Density Functional Theory (DFT) methods. Sulfone derivatives were shown to be high performing TADF emitters over recent years. When discussing the TADF efficiency, various properties, such as, singlet–triplet energy gap (∆EST), spin–orbit coupling (SOC), nature of states and the hyperfine coupling (HF) stand out due to their roles in reverse intersystem crossing (RISC). Here, we mainly focused on three important structural parameters that affect the intersystem crossing (ISC) and RISC pathways and their efficiencies. These three parameters are: 1) effect of meta- and para- conjugation, 2) effect of rigid acceptor moieties and 3) effect of phenyl bridge on photophysical properties.