Transient absorption spectroscopy detection of sensitized delayed fluorescence in chiral benzophenone/naphthalene systems
نویسندگان
چکیده
Transient absorption spectroscopy has proven to be a powerful tool to investigate the formation and decay of excited singlet states upon triplet-triplet annihilation, following T-T energy transfer from a selectively excited sensitizer. Thus, upon selective excitation of benzophenone (BZP) by laser flash photolysis (LFP) at λ = 355 nm in the presence of naphthalene (NPT), a negative band centred at 340 nm has been detected, with growth and decay in the microsecond timescale. It has been assigned to the P-type NPT delayed-fluorescence. In the case of chiral BZP/NPT systems, stereodifferentiation has been observed in the kinetics of the involved photophysical processes.
منابع مشابه
Fast transient absorption spectroscopy of the early events in photoexcited chiral benzophenone–naphthalene dyads
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