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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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Collision dynamics of proton with formaldehyde: fragmentation and ionization
Jing Wang1, Cong-Zhang Gao1, Florent Calvayrac2
1The Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875, China.
The Journal of Chemical Physics
|April 5, 2014
Summary
This study investigates formaldehyde ionization and fragmentation during proton collisions, revealing that collision energy and orientation significantly impact outcomes at low impact parameters.
Area of Science:
- Atomic and Molecular Physics
- Quantum Chemistry
- Chemical Dynamics
Background:
- Formaldehyde is a key molecule in atmospheric and interstellar chemistry.
- Understanding its interactions with charged particles is crucial for astrophysical models.
- Proton impact ionization and fragmentation are fundamental processes.
Purpose of the Study:
- To investigate the ionization and fragmentation of formaldehyde upon proton impact.
- To analyze the influence of collision energy and projectile orientation (steric effects) on the reaction dynamics.
- To calculate cross sections for electron ionization and fragmentation patterns.
Main Methods:
- Time-dependent density functional theory (TDDFT) for valence electrons.
- Non-adiabatic coupling to molecular dynamics of ions.
- Simulations at four impact energies (35-300 eV) and ten orientations at 85 eV.
Main Results:
- Calculated fragmentation ratios, single, double, and total electron ionization cross sections.
- Observed strong dependence of results on collision energy and orientation at small impact parameters.
- Noted negligible outcomes for large impact parameters due to weak interaction.
Conclusions:
- Collision energy and orientation are critical factors in formaldehyde's ionization and fragmentation by protons.
- The study provides detailed insights into reaction channels and fragment distributions.
- Results are essential for accurate modeling of chemical processes in various environments.
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