Femtosecond Transient Absorption Studies of - ACS Publications

While the trans isomer takes 150-300 ps to fully recover the bleach, the cis isomer requires ..... on the lifetime of the 2A state in the gas phase ga...
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J. Phys. Chem. A 1998, 102, 35-44

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Femtosecond Transient Absorption Studies of trans- and cis-1,3,5-Hexatriene in Solution Kaoru Ohta,†,‡ Yukito Naitoh,‡ Keisuke Tominaga,‡ Noboru Hirota,† and Keitaro Yoshihara*,‡ Department of Chemistry, Graduate School of Science, Kyoto UniVersity, Kyoto 606, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444, Japan ReceiVed: August 8, 1997; In Final Form: October 17, 1997X

The electronic, vibrational and conformational relaxation of trans- and cis-1,3,5-hexatriene in solution have been investigated by femtosecond transient absorption spectroscopy. Upon excitation to the 1B state, the transient absorption is observed in the visible region, which mainly consists of an instantaneous rise (