Direct versus indirect H atom elimination from photoexcited phenol molecules.
The active role of the optically dark pi sigma* state, following UV absorption, has been implicated in the photochemistry of a number of biomolecules. This work focuses on the role of the pi sigma* state in the photochemistry of phenol upon excitation at 200 nm. By probing the neutral hydrogen following UV excitation, we show that hydrogen elimination along the dissociative pi sigma* potential energy surface occurs within 103 +/- 30 fs, indicating efficient coupling at the S1/S2 and S0/S2 conical intersections, with no identifiable role of statistical unimolecular decay of vibronically excited (S0) phenol in the timeframe of our measurements.
Iqbal
Azhar
A
Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK.
Pegg
Lara-Jane
LJ
Stavros
Vasilios G
VG
D004735:Energy Transfer; D005453:Fluorescence; D006859:Hydrogen / Q000737:chemistry*; D019800:Phenol / Q000737:chemistry*; D010777:Photochemistry; D017785:Photons; D014466:Ultraviolet Rays; D014732:Vibration
D019800:Phenol; D006859:Hydrogen