Attosecond timing of electron emission from a molecular shape resonance

Research output: Contribution to journalArticle


Shape resonances in physics and chemistry arise from the spatial confinement of a particle by a potential barrier. In molecular photoionization, these barriers prevent the electron from escaping instantaneously, so that nuclei may move and modify the potential, thereby affecting the ionization process. By using an attosecond two-color interferometric approach in combination with high spectral resolution, we have captured the changes induced by the nuclear motion on the centrifugal barrier that sustains the well-known shape resonance in valence-ionized N2. We show that despite the nuclear motion altering the bond length by only 2%, which leads to tiny changes in the potential barrier, the corresponding change in the ionization time can be as large as 200 attoseconds. This result poses limits to the concept of instantaneous electronic transitions in molecules, which is at the basis of the Franck-Condon principle of molecular spectroscopy.


External organisations
  • Claude Bernard University Lyon 1
  • Autonomous University of Madrid
  • University of Gothenburg
  • IMDEA Nanociencia
  • Condensed Matter Physics Center (IFIMAC)
  • Donostia International Physics Center (DIPC)
  • University of Trieste
  • CNR Istituto Officina dei Materiali (IOM)
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Atom and Molecular Physics and Optics
Original languageEnglish
Pages (from-to)eaba7762
JournalScience Advances
Issue number31
Publication statusPublished - 2020
Publication categoryResearch