Time resolved MARY spectra in the photo cleavage of TMDPO
نویسندگان
چکیده
The time resolved feature of the MARY (Magnetic field effect on Reaction Yield) spectra is studied in the system of Diphenyl(2,4,6-trimethyl-benzoyl)phosphineoxide (TMDPO) in micelle. Two kinds of magnetic field effects (MFE) can be distinguished in the different time scales. First one is generated in the time scale less than 50 ns and negative (decrease the transient absorption in comparison with that at zero magnetic field) at less than 100mT and positive at larger than 100mT. Second one has only positive effect and more apparent at larger than 100mT. The rapid component is rationalized as the hyperfine induced mechanisms, and slow rise component is assigned to the relaxation mechanisms. By the theoretical model calculation, it is indicated that the primary diffusion process of the radical pair plays an important role on the MARY time profile especially in the system with large hyperfine coupling constant like the system of TMDPO.
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