| Abstrakt: |
In order to get insight into the effect of the different fixations of the conjugated systems of the aminochalcone-dyes on both the photophysical behavior and the quenching scheme of photoinitiation systems in a film, photophysical behavior of 2-benzoyl-6-(dimethylamino)benzo[b]furan (A) on 355 nm excitation with or without a radical-generating reagent, 2,4,6-tris(trichloromethyl)-1,3,5-triazine (TRI), in poly(methyl methacrylate) (PMMA) film has been investigated by laser flash photolysis using a total reflection cell. Dye Ashowed characteristic dual fluorescences of which the lifetimes, τSs, of shorter- and longer-wavelength components were evaluated to be 3.2 and 5.4 ns, respectively. The fluorescences were quenched by TRIwith different static quenching distances, (Rs)Ss, of 1.3 and 1.5 nm for Ashortand Along, respectively. The static quenching distance of the initial triplet absorption of A, (Rs)T, was evaluated to be 1.5 nm. In addition, deconvolution analysis of the lifetimes of fluorescent dyes has been carried out to clarify the property of nonstatic quenching of the dyes: A, 10-benzoyl-2,3,6,7-tetrahydro-1H,5H-furo[3,2-g]pyrido[3,2,1-i,j]quinoline (B), 4′-(dimethylamino)chalcone (C), and (E)-3-(9-julolidinyl)-1-phenyl-2-propen-1-one (D), with TRIin the film. |
