Femtosecond Raman spectra of cis-stilbene and trans-stilbene with isotopomers in solution.
J Chem Phys
; 137(24): 244505, 2012 Dec 28.
Article
en En
| MEDLINE
| ID: mdl-23277943
Femtosecond stimulated Raman spectra of trans-stilbene (D0), its isotopomers D2, D10, D12, (13)C2 and of cis-stilbene in hexane are measured in the ground (S(0)) and excited (S(1)) electronic states. The ground (13)C2 and excited D12 spectra are presented for the first time; the excited cis-spectra differ substantially from previously published ones. S(1) Raman bands of trans-stilbene are 20 cm(-1) wide corresponding to ~1 ps vibrational dephasing. For cis-stilbene the bands are broadened to 40 cm(-1) reflecting a short excited-state lifetime of 0.3 ps, in agreement with transient absorption data. From a dynamic shift of the 1569 cm(-1) band, pump-induced intramolecular cooling is estimated to be less than 20 K. Many S(1) Raman lines are detected for the first time. Vibrational spectra are calculated at MP2/cc-pVTZ (for S(0)) and XMCQDPT2/cc-pVTZ (for S(1)) levels of theory. Experimental and computational results can be used for a re-evalution of Rice-Ramsberger-Kassel-Marcus (RRKM) predictions for this famous photoisomeration reaction.
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01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
J Chem Phys
Año:
2012
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Estados Unidos