Resonant Auger decay induced by the symmetry-forbidden 1a_1g → 6a_1g transition of the SF₆ molecule

Antonio Santos (1) , Oksana Travnikova (2, 3) , Nacer Boudjemia (2, 4) , Tatiana Marchenko (2, 3) , Renaud Guillemin (2, 3) , Iyas Ismail (2, 3) , Dimitris Koulentianos (2, 5, 6) , Denis Céolin (3) , Faris Gel'Mukhanov (7) , Marc Simon (2, 3) , Maria Novella Piancastelli (2, 8) , Ralph Püttner (9)

1 IF / UFRJ - Instituto de Física da Universidade Federal do Rio de Janeiro
2 LCPMR - Laboratoire de Chimie Physique - Matière et Rayonnement
3 SSOLEIL - Synchrotron SOLEIL
4 NMSRU - Nano and Molecular Systems Research Unit
5 GU - Göteborgs Universitet = University of Gothenburg
6 DESY - Deutsches Elektronen-Synchrotron [Hamburg]
7 KTH - KTH Royal Institute of Technology [Stockholm]
8 Department of Physics and Astronomy [Uppsala]
9 Freie Universität Berlin

Resonant Auger electron spectroscopic study at the symmetry-forbidden [Formula: see text] excitation below the S [Formula: see text]-shell threshold of SF[Formula: see text] is reported. Partial electron yield and resonant [Formula: see text] Auger spectra have been measured by using monochromatized undulator synchrotron radiation. By changing the photon energy in small steps, a so-called 2D map is produced. In this map, the dipole-forbidden transition exhibits spectral features (e.g., an S-shaped dispersion relation), which are well known and understood for dipole-allowed transitions. We validate by a theory that for the case of dipole-forbidden transitions, these spectral features can be analyzed in the same way as previously established for the dipole-allowed ones. This approach grants information on the nuclear dynamics in the [Formula: see text]-shell core-excited states of SF[Formula: see text] on the femtosecond (fs) timescale. In particular, for the potential-energy curves of the states S [Formula: see text] and S [Formula: see text], the slopes at the equilibrium distance of the ground state are derived. Symmetry breaking as a result of ultrafast vibronic coupling is revealed by the population of the electronically forbidden excited state.

Domaines: Chimie-Physique [physics.chem-ph]

Antonio Santos, Oksana Travnikova, Nacer Boudjemia, Tatiana Marchenko, Renaud Guillemin, et al.. Resonant Auger decay induced by the symmetry-forbidden 1a_1g → 6a_1g transition of the SF₆ molecule. Journal of Vacuum Science & Technology A, 2022, Special Collection: Commemorating the Career of David Arthur Shirley, 40 (4), pp.042801. ⟨10.1116/6.0001890⟩. ⟨hal-03797323⟩