Tuning the photophysical properties of 4′-substituted terpyridines - an experimental and theoretical study

Several 2,2':6',2 ''-terpyridines substituted in the 4'-position were synthesized and their photophysical properties were investigated by absorption and photoluminescence spectroscopy in dilute solutions and solid state. The studies confirmed that the absorption and emission wavelengths, fluorescence quantum yields and lifetimes of 1-R1-16 are strongly structure-related, demonstrating a decisive role of the nature of the substituent in determining the photophysical properties of 4'-functionalized terpyridines. Additionally, the density functional theory (DFT) calculations were performed for 1-R1-16 to get insight into their electronic structure and spectroscopic properties.