title: Trapped Hydronium Radical Produced by Ultraviolet Excitation of Substituted Aromatic Molecule.
abstract: The gas phase structure and excited state dynamics of o-aminophenol-H2O complex have been investigated using REMPI, IR-UV hole-burning spectroscopy, and pump-probe experiments with picoseconds laser pulses. The IR-UV spectroscopy indicates that the isomer responsible for the excitation spectrum corresponds to an orientation of the OH bond away from the NH2 group. The water molecule acts as H-bond acceptor of the OH group of the chromophore. The complexation of o-aminophenol with one water molecule induced an enhancement in the excited state lifetime on the band origin. The variation of the excited state lifetime of the complex with the excess energy from 1.4 ± 0.1 ns for the 0-0 band to 0.24 ± 0.3 ns for the band at 0-0 + 120 cm(-1) is very similar to the variation observed in the phenol-NH3 system. This experimental result suggests that the excited state hydrogen transfer reaction is the dominant channel for the non radiative pathway. Indeed, excited state ab initio calculations demonstrate that H transfer leading to the formation of the H3O(•) radical within the complex is the main reactive pathway.
authors.affiliation: Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET - UNC. Dpto. de Fisicoquímica - Facultad de Ciencias Químicas, Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria , X5000HUA Córdoba, Argentina.
authors.forename: Federico J
authors.initials: FJ
authors.lastname: Hernández
authors.affiliation: Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET - UNC. Dpto. de Fisicoquímica - Facultad de Ciencias Químicas, Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria , X5000HUA Córdoba, Argentina.
authors.forename: Marcela C
authors.initials: MC
authors.lastname: Capello
authors.affiliation: Chemical Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology , 4259 Nagatsuta , Midori-ku,Yokohama 226-8503, Japan.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Naito
authors.affiliation: Chemical Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology , 4259 Nagatsuta , Midori-ku,Yokohama 226-8503, Japan.
authors.forename: Shun
authors.initials: S
authors.lastname: Manita
authors.affiliation: Chemical Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology , 4259 Nagatsuta , Midori-ku,Yokohama 226-8503, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Tsukada
authors.affiliation: Chemical Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology , 4259 Nagatsuta , Midori-ku,Yokohama 226-8503, Japan.
authors.forename: Mitsuhiko
authors.initials: M
authors.lastname: Miyazaki
authors.affiliation: Chemical Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology , 4259 Nagatsuta , Midori-ku,Yokohama 226-8503, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Fujii
authors.affiliation: Centre Laser de l'Université Paris Sud (CLUPS/LUMAT), Université Paris-Sud, CNRS, Institut d'Optique Graduate School, Université Paris-Saclay , F-91405 Orsay, France.|Institut des Sciences Moléculaires d'Orsay (ISMO), CNRS, Université Paris-Sud, Université Paris-Saclay , F-91405 Orsay, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Broquier
authors.affiliation: Centre Laser de l'Université Paris Sud (CLUPS/LUMAT), Université Paris-Sud, CNRS, Institut d'Optique Graduate School, Université Paris-Saclay , F-91405 Orsay, France.|Institut des Sciences Moléculaires d'Orsay (ISMO), CNRS, Université Paris-Sud, Université Paris-Saclay , F-91405 Orsay, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Gregoire
authors.affiliation: Aix Marseille Université, CNRS , PIIM UMR 7345, 13397, Marseille, France.
authors.forename: Claude
authors.initials: C
authors.lastname: Dedonder-Lardeux
authors.affiliation: Aix Marseille Université, CNRS , PIIM UMR 7345, 13397, Marseille, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Jouvet
authors.affiliation: Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET - UNC. Dpto. de Fisicoquímica - Facultad de Ciencias Químicas, Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria , X5000HUA Córdoba, Argentina.
authors.forename: Gustavo A
authors.initials: GA
authors.lastname: Pino