Photophysical and Photochemical Properties of 2,3-Dihydro-4(l H)-quinolinones. Part I. Fluorescence Properties
نویسنده
چکیده
Absorption spectra and fluorescence properties o f 2,3-dihydro-4( 1 H)-quinolinone deriva tives were studied at room temperature in different solvents. It has been found that the fluo rescence quantum yields and fluorescence decay times strongly depend on the molecular struc ture and solvent polarity. The character and the energy o f excited states were determined by PPP and CNDO /S quantum-chemical calculations.
منابع مشابه
Photophysical and Photochemical Properties of 2,3-Dihydro-4(l H)- quinolinones. Part II. Rates and Mechanism of Primary Processes
Fluorescence quantum yields, singlet lifetimes and triplet yields for 2-methyl-2,3-dihydro4(1 H)-quinolinone and N-methyl-2,3-dihydro-4(l H)-quinolinone were determined as a func tion o f temperature. In non-polar solvents, an efficient non-radiative process identified as an indirect singlet —*• triplet transition occurring through S2(n,jr*) was found to depopulate the lowest S 1(7t,7E*) state...
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