Nature of the S2-state quenching process of benzopyranthione by hydrocarbon solvents measured by pico- and femtosecond laser spectroscopy

被引:19
作者
Burdzinski, G
Maciejewski, A
Buntinx, G
Poizat, O
Lefumeux, C
机构
[1] Adam Mickiewicz Univ Poznan, Fac Chem, Photochem Lab, PL-60780 Poznan, Poland
[2] Univ Lille 1, Ctr Etud & Rech Lasers & Applicat, CNRS, LASIR, F-59655 Villeneuve Dascq, France
[3] Adam Mickiewicz Univ Poznan, Fac Phys, Quantum Elect Lab, PL-61614 Poznan, Poland
关键词
D O I
10.1016/S0009-2614(02)01926-7
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Femtosecond transient absorption has been used to study the mechanism and dynamics of the quenching of an aromatic thioketone, 4H-1-benzopyrane-4-thione (BPT), in the S-2 state, by saturated hydrocarbons (n-hexane, dodecane, hexadecane, cyclohexane, cyclohexane-d(12)). The results demonstrate the involvement of the hydrocarbon C-H bonds in the quenching process. Two quenching mechanisms are proposed: efficient H-atom abstraction followed by ultrafast back hydrogen transfer, or 'aborted hydrogen abstraction'. In the latter case, the progress along the reaction path to a conical intersection is assumed to deactivate the S-2 state through transition to the S, state energy surface. (C) 2003 Elsevier Science B.V. All rights reserved.
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收藏
页码:745 / 753
页数:9
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