Excited-state vibrational coherence of solution-phase molecules observed in the third-order optical process using extremely short pulses
نویسندگان
چکیده
Excited-state vibrational coherence of solution-phase polyatomic molecules was studied by two different timedomain spectroscopic methods. Raman-active low-frequency vibrations in the excited state of trans-stilbene were observed by transient impulsive stimulated Raman scattering spectroscopy. In transient absorption spectroscopy with a 40-fs resolution, a different vibrational mode of the same excited state was observed as a “beat” in the pump-induced absorption signal. We discussed the selection of the vibrational modes by noting the difference in the third-order optical processes relevant to the two spectroscopies. The vibrational coherence of a “reacting” excited state was also observed for ultrafast photodissociation of diphenylcyclopropenone.
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