Téléchargement | - Voir le manuscrit accepté : Ultrafast dynamics of o-nitrophenol: An experimental and theoretical study (PDF, 1.4 Mio)
|
---|
DOI | Trouver le DOI : https://doi.org/10.1021/acs.jpca.5b04900 |
---|
Auteur | Rechercher : Ernst, Hanna A.; Rechercher : Wolf, Thomas J. A.; Rechercher : Schalk, Oliver1; Rechercher : González-García, Nuria; Rechercher : Boguslavskiy, Andrey E.2; Rechercher : Stolow, Albert2; Rechercher : Olzmann, Matthias; Rechercher : Unterreiner, Andreas-Neil |
---|
Affiliation | - Conseil national de recherches du Canada. Institut Steacie des sciences moléculaires du CNRC
- Conseil national de recherches du Canada. Technologies de sécurité et de rupture
|
---|
Format | Texte, Article |
---|
Sujet | Absorption spectroscopy; Atmospheric chemistry; Charge transfer; Gases; Ground state; Inorganic acids; Ionization of gases; Phenols; Photoelectron spectroscopy; Photoelectrons; Photolysis; Photons; Proton transfer; Quantum chemistry; Quantum theory; Excited-state proton transfer; Femtosecond transient absorption spectroscopy; Inter-system crossings; Out-of-plane rotation; Photoelectron spectrum; Quantum chemical calculations; Subpicosecond time scale; Time-resolved photoelectron spectroscopy |
---|
Résumé | The photolysis of o-nitrophenol (o-NP), a typical push-pull molecule, is of current interest in atmospheric chemistry as a possible source of nitrous acid (HONO). To characterize the largely unknown photolysis mechanism, the dynamics of the lowest lying excited singlet state (S<inf>1</inf>) of o-NP was investigated by means of femtosecond transient absorption spectroscopy in solution, time-resolved photoelectron spectroscopy (TRPES) in the gas phase and quantum chemical calculations. Evidence of the unstable aci-nitro isomer is provided both in the liquid and in the gas phase. Our results indicate that the S<inf>1</inf> state displays strong charge transfer character, which triggers excited state proton transfer from the OH to the NO<inf>2</inf> group as evidenced by a temporal shift of 20 fs of the onset of the photoelectron spectrum. The proton transfer itself is found to be coupled to an out-of-plane rotation of the newly formed HONO group, finally leading to a conical intersection between S<inf>1</inf> and the ground state S<inf>0</inf>. In solution, return to S<inf>0</inf> within 0.2-0.3 ps was monitored by stimulated emission. As a competitive relaxation channel, ultrafast intersystem crossing to the upper triplet manifold on a subpicosecond time scale occurs both in solution and in the gas phase. Due to the ultrafast singlet dynamics, we conclude that the much discussed HONO split-off is likely to take place in the triplet manifold. |
---|
Date de publication | 2015-08-12 |
---|
Dans | |
---|
Langue | anglais |
---|
Publications évaluées par des pairs | Oui |
---|
Numéro NPARC | 21276968 |
---|
Exporter la notice | Exporter en format RIS |
---|
Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
---|
Identificateur de l’enregistrement | ce83ef5b-a095-4e1f-85dd-e4e329f4a190 |
---|
Enregistrement créé | 2015-11-10 |
---|
Enregistrement modifié | 2020-06-04 |
---|