title: Aromatic ring size effects on the photophysics and photochemistry of styrylbenzothiazole.
abstract: The effect of ring size on the photophysics and photochemistry of styrylbenzothiazole has been investigated via systematic replacement of the phenyl ring of 1-phenyl-2-(2-benzothiazolyl)ethene with naphthyl and phenanthryl rings. Steady state absorption and fluorescence techniques have been employed to record the spectra in a variety of solvents, in conjunction with density functional theory (DFT) calculations, to probe absorption spectra and other properties of relevance to photo-excitation. Important experimental parameters were determined, such as fluorescence quantum yield and quantum yields of photochemical E-Z isomerisation. In addition, the computed potential energy surfaces of the ground and excited states were constructed using DFT/TD-DFT methods that showed that the photo-reaction is based on an adiabatic mechanism, in the sense that the reaction occurs via the excited-state potential energy surface. Based on the significant blue shift of the Z-isomer absorption maximum relative to that of the E-isomer, and the high percentage of Z-isomers in the photo-stationary state, these compounds may serve as potential promising candidates for optical data storage applications.
authors: Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt. mohamed.awad1@science.tanta.edu.eg
authors: Mohamed K
authors: MK
authors: Awad
authors: Morad M
authors: MM
authors: El-Hendawy
authors: Tarek A
authors: TA
authors: Fayed
authors: Safaa Eldin H
authors: SE
authors: Etaiw
authors: Niall J
authors: NJ
authors: English