Transient absorption and vibrational relaxation dynamics of the lowest excited singlet state of pyrene in solution
Anno: 1995
Autori: Foggi P., Pettini L., Sànta I., Righini R., Califano S.
Affiliazione autori: Institute of Physics, Janus Pannonius University, Pécs, Hungary
Abstract: The spectrum of highly excited electronic states of pyrene in n-octane solution and the relaxation processes in the S1 singlet state are investigated by femtosecond transient absorption spectroscopy. Three different UV excitation wavelengths (360, 307, and 290 nm) are utilized to excite the molecule at the edge of the S1 ? S0 transition and to higher Sn ? S0 transitions. The buildup of S1 population has been observed to be completed in the first 2 ps, with a time constant of 300-400 fs, depending on the excitation wavelength. The evolution of the absorption spectra on a larger time scale is attributed to the vibrational cooling in the S1 state; its rate corresponds to an exponential relaxation with time constant of about 4 ps. The evidence of the formation of pyrene excimer at long time delays in highly concentrated solutions is reported.
Giornale/Rivista: JOURNAL OF PHYSICAL CHEMISTRY
Volume: 99 (19) Da Pagina: 7439 A: 7445
Parole chiavi: Emission-spectra; ExcitationDOI: 10.1021/j100019a029Citazioni: 58dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2024-04-28Riferimenti tratti da Isi Web of Knowledge: (solo abbonati) Link per visualizzare la scheda su IsiWeb: Clicca quiLink per visualizzare la citazioni su IsiWeb: Clicca qui