title: Ultrafast photophysics of the isolated indole molecule.
abstract: 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 ππ* L(b) and L(a) states, and the dark πσ* state with dissociative character. In the low energy region (λ > 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 ~400 fs component, found at excitation wavelengths shorter than 263 nm, is ascribed to dynamics along the πσ* 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.
authors: Departamento de Química-Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco (UPV/EHU), Apart. 644, 48080 Bilbao, Spain.
authors: Raúl
authors: R
authors: Montero
authors: Álvaro Peralta
authors: ÁP
authors: Conde
authors: Virginia
authors: V
authors: Ovejas
authors: Fernando
authors: F
authors: Castaño
authors: Asier
authors: A
authors: Longarte
mesh_terms: D016880:Anisotropy; D004583:Electrons; D007211:Indoles / Q000737:chemistry*; D055668:Photochemical Processes; D011789:Quantum Theory; D013816:Thermodynamics; D013997:Time Factors; D014364:Tryptophan / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: D007211:Indoles; C030374:indole; D014364:Tryptophan