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Updated: Jun 1, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Communication: mode-specific photodissociation of vibrationally excited pyrrole
Michael Epshtein1, Alexander Portnov, Salman Rosenwaks
1Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
Abstract:
Laser-based spectroscopies coupled with molecular beam techniques facilitated the monitoring of H fragments released in ultraviolet photodissociation of pre-excited isoenergetic vibrational levels of pyrrole. Most noticeably, there was an order of magnitude larger reactivity for an eigenstate primarily consisting of two quanta of ring deformation than for another with one quantum of symmetric C-H stretch. The dynamics, the intramolecular interactions controlling the energy flow, and the mode-selectivity within a medium-sized, ten atom molecule, is discussed.
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