Amelle: Conical Intersection Dynamics in NO2 Probed by Homodyne High-Harmonic Spectroscopy

Conical Intersection Dynamics in NO₂ Probed by Homodyne High-Harmonic Spectroscopy

1. H. J. Wörner¹,²,*, 
2. J. B. Bertrand¹, 
3. B. Fabre³, 
4. J. Higuet³, 
5. H. Ruf³, 
6. A. Dubrouil³, 
7. S. Patchkovskii¹, 
8. M. Spanner¹,
9. Y. Mairesse³, 
10. V. Blanchet⁴, 
11. E. Mével³, 
12. E. Constant³, 
13. P. B. Corkum¹, 
14. D. M. Villeneuve¹

+Author Affiliations

1. ¹Joint Laboratory for Attosecond Science, National Research Council of Canada and University of Ottawa, 100 Sussex Drive, Ottawa, Ontario, Canada K1A 0R6.
2. ²Laboratorium für Physikalische Chemie, Eidgenössische Technische Hochschule Zürich, Wolfgang-Pauli-Strasse 10, 8093 Zürich, Switzerland.
3. ³Centre Lasers Intenses et Applications, Université de Bordeaux, CEA, CNRS, UMR5107, 351 Cours de la Libération, 33405 Talence, France.
4. ⁴Laboratoire Collisions Agrégats Réactivité (IRSAMC), UPS, Université de Toulouse, F-31062 Toulouse, France and CNRS, UMR 5589, F-31062 Toulouse, France

1. ↵*To whom correspondence should be addressed. E-mail: woerner@phys.chem.ethz.ch

ABSTRACT

Conical intersections play a crucial role in the chemistry of most polyatomic molecules, ranging from the simplest bimolecular reactions to the photostability of DNA. The real-time study of the associated electronic dynamics poses a major challenge to the latest techniques of ultrafast measurement. We show that high-harmonic spectroscopy reveals oscillations in the electronic character that occur in nitrogen dioxide when a photoexcited wave packet crosses a conical intersection. At longer delays, we observe the onset of statistical dissociation dynamics. The present results demonstrate that high-harmonic spectroscopy could become a powerful tool to highlight electronic dynamics occurring along nonadiabatic chemical reaction pathways.

http://www.sciencemag.org/content/334/6053/208