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Stephane Carniato

Publications and source records attributed to Stephane Carniato.

2 recordsLinked to original sources

Ionic photofragmentation cross sections of the HS+ H2S+ and HCl+ molecular ions near the 2p threshold

The absolute cross sections for the production of X2+ and X3+ ions following absorption of monochromatized SOLEIL synchrotron radiation by the HX+ hydride molecular ions (X = S,Cl) are presented as a function of photon energy in the region of the X 2p ionisation thresholds (180 eV and 220 eV for sulphur and chlorine, respectively). The experimental results are interpreted with the help of extensive ab initio density functional theory (DFT) and post-Hartree-Fock configuration interaction calculations including spin-orbit coupling to compute the absorption oscillator strengths of the X 2p core excitations to valence and Rydberg states. In order to account for all the experimental features,the calculations must include vibrational dynamics and spin-orbit coupling. Similar experimental data are also presented for the sulfanyumil H2S+ molecular ion.

physics.atom-ph

Ultrafast Nuclear Dynamics in Double-Core Ionized Water Molecules

Double-core-hole (DCH) states in isolated water and heavy water molecules, resulting from the sequential absorption of two x-ray photons, have been investigated. A comparison of the subsequent Auger emission spectra from the two isotopes provides direct evidence of ultrafast nuclear motion during the 1.5 fs lifetime of these DCH states. Our numerical results align well with the experimental data, providing for various DCH states an in-depth study of the dynamics responsible of the observed isotope effect.

physics.chem-ph