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An Experimental Protocol for Femtosecond NIR/UV - XUV Pump-Probe Experiments with Free-Electron Lasers
Published on: October 23, 2018
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Charge and Nuclear Dynamics Induced by Deep Inner-Shell Multiphoton Ionization of CH3I Molecules by Intense X-ray
Koji Motomura1, Edwin Kukk1,2, Hironobu Fukuzawa1,3
1†Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan.
The Journal of Physical Chemistry Letters
|August 13, 2015
Summary
Free-electron lasers enable studying femtosecond dynamics after deep inner-shell ionization. Investigating charge dynamics in molecular Coulomb explosion is crucial for understanding ultrashort X-ray pulse interactions with molecules like CH3I.
Area of Science:
- Atomic and Molecular Physics
- Ultrafast Science
- X-ray Science
Background:
- Free-electron lasers (FELs) provide unprecedented access to femtosecond dynamics.
- Deep inner-shell ionization initiates complex charge creation and transfer processes.
- Molecular Coulomb explosion is a key phenomenon studied with intense ultrashort pulses.
Purpose of the Study:
- To investigate charge creation and transfer dynamics in molecular Coulomb explosion.
- To analyze single-molecule charge states induced by sequential deep inner-shell ionization.
- To compare experimental data with a parametric model of charge dynamics.
Main Methods:
- Utilized ultrashort (10 fs) X-ray pulses from a free-electron laser.
- Employed time-of-flight ion spectroscopy and coincident ion analysis.
- Studied the methyl iodide (CH3I) molecule, sensitized by iodine for X-ray absorption.
Main Results:
- Determined single-molecule charge states reaching up to +22.
- Observed complex charge creation and transfer dynamics.
- Experimental results align with a parametric model incorporating charge dynamics.
Conclusions:
- Realistic charge dynamics are essential for interpreting molecular Coulomb explosion experiments.
- Femtosecond X-ray pulses reveal intricate molecular responses to ionization.
- This study advances the understanding of molecular fragmentation under extreme conditions.
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