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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Electron rearrangement dynamics in dissociating I(2)^(n+) molecules accessed by extreme ultraviolet pump-probe
K Schnorr1, A Senftleben1, M Kurka1
1Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany.
Physical Review Letters
|August 30, 2014
Summary
Researchers measured charge rearrangement in dissociating iodine molecules (I2n+) using extreme ultraviolet pulses. Electron transfer between fragments at specific internuclear distances validated the classical over-the-barrier model.
Area of Science:
- Chemical Physics
- Atomic, Molecular, and Optical Physics
- Quantum Chemistry
Background:
- Understanding charge dynamics in dissociating molecules is crucial for fields like plasma physics and chemistry.
- Free-electron lasers (FELs) offer unique capabilities for probing ultrafast molecular processes.
Purpose of the Study:
- To investigate charge rearrangement in dissociating I2n+ molecules as a function of internuclear distance.
- To validate theoretical models for charge transfer in quasimolecular systems.
Main Methods:
- Utilized an extreme ultraviolet (XUV) pump-probe spectroscopy scheme with an FEL.
- Initiated dissociation with an XUV pulse and triggered charge rearrangement with a delayed XUV probe pulse.
- Monitored electron transfer by analyzing ion kinetic energies and charge states.
Main Results:
- Successfully measured charge rearrangement during I2n+ dissociation at well-defined internuclear distances.
- Observed electron transfer dynamics between molecular fragments.
- Experimental data showed excellent agreement with the classical over-the-barrier model.
Conclusions:
- The classical over-the-barrier model accurately describes charge transfer in the studied quasimolecular regime.
- Findings are relevant for free-electron laser applications, plasma physics, and chemical dynamics.
- Demonstrated the capability of XUV pump-probe spectroscopy for probing molecular charge dynamics.
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