Intramolecular charge transfer and electronic absorption and luminescence spectra of fluoroquinolinones

TD-DFT study on the effect of donor and acceptor substituents on molecular orbital localization and charge distribution in fluoroquinolinone molecules showed that their photoexcitation is accompanied by electron density redistribution over particular fragments. Depending on the protolytic form, frontier molecular orbitals are localized on different fragments, whereas variation of substituents weakly affects localization of these orbitals.