On the properties of new benzothiazole derivatives for organic light emitting diodes (OLEDs): A comprehensive theoretical study

The present investigation explored theoretically the geometry structures, the electronic and the optical properties of new benzothiazole derivatives with incorporated triphenylamine/diphenylnaphthylamine or (4-vinylphenyl)acrylonitrile as highly efficient emitting molecular materials for organic light emitting diodes (OLEDs). This study is accomplished in order to provide an in-depth understanding of the structure–properties correlation and their effects on optoelectronic devices.In this contribution, we apply quantum-chemical methods (semiempirical Austin Model 1 (AM1), ab-initio Hartree–Fock (HF) and density functional theory (DFT)) to elucidate the photophysical properties of these molecules. First of all, the geometry structures of these compounds in the ground and the excited states were fully optimized, showing a non-planar configuration structures. Whereas, the geometrical structure of benzothiazole with cyano-PV unit is more planar. Structural parameters and vibrational properties of these compounds are then derived. Moreover, absorption and luminescence properties, lying in a bluish white or red light emission, were elucidated by ZINDO/S methods. The molecular orbital (highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO)), the ionization potentials (IPs) and the electron affinities (EAs) of compounds under study were also investigated. It was found that the detailed results obtained from theoretical simulations are consistent with the available experimental data. This kind of theoretical approach has been proved to be reliable for the structure and spectroscopic properties, and predicts the favorable qualities of these benzothiazole derivatives, which make them as the materials of choice for high performance applications.