Ultrafast Photophysics of the Isolated Indole Molecule

作者：Montero Raul; Conde Alvaro Peralta; Ovejas Virginia; Castano Fernando; Longarte Asier^*

来源：Journal of Physical Chemistry A, 2012, 116(11): 2698-2703.

DOI：10.1021/jp207750y

The relaxation dynamics of the isolated indole molecule has been tracked by femtosecond time-resolved ionization. The excitation region explored (283-243 nm) covers three excited states: the two pi* L-b and L-a states, and the dark pi sigma* state with dissociative character. In the low energy region (lambda %26gt; 273 nm) the transients collected reflect the absorption of the long living L-b state. The L-a state is met 1000-1500 cm(-1) above the L-b origin, giving rise to an ultrafast lifetime of 40 fs caused by the internal conversion to the lower L-b minimum through a conical intersection. An additional similar to 400 fs component, found at excitation wavelengths shorter than 263 nm, is ascribed to dynamics along the pi sigma* state, which is likely populated through coupling to the photoexcited L-a state. The study provides a general view of the indole photophysics, which is driven by the interplay between these three excited surfaces and the ground state.

• 出版日期2012-3-22