Proton migration in hydrocarbons induced by slow highly charged ion impact
1Department of Nuclear Science and Technology, Institute of Modern Physics, Fudan University, Shanghai 200433, China.
The Journal of Chemical Physics
|June 3, 2019
Summary
Highly charged ions induce proton migration in methane and acetylene molecules. Researchers observed new H3+ formation and isomerization pathways, gaining insights into hydrocarbon dication fragmentation.
Area of Science:
- Atomic and Molecular Physics
- Chemical Physics
- Physical Chemistry
Background:
- Proton migration is a fundamental process in chemistry.
- Previous studies often used photons to induce molecular changes.
- Understanding hydrocarbon dication fragmentation is crucial for chemical dynamics.
Purpose of the Study:
- To investigate proton migration in methane (CH4) and acetylene (C2H2) using highly charged ions.
- To identify and characterize new fragmentation and isomerization channels.
- To obtain kinetic energy release data for dication fragmentation.
Main Methods:
- Collision experiments using highly charged ions as projectiles.
- Analysis of fragmentation patterns of methane and acetylene dications.
- Measurement of kinetic energy release spectra for dissociation channels.
Main Results:
- Observed H3+ formation (H3+ + CH+) and isomerization (C+ + CH2+) channels in CH4 and C2H2 dications.
- Obtained kinetic energy release data for the first time in such collisions.
- Identified a new isomerization pathway (C+ + CH2+) attributed to high-lying states of acetylene dication.
Conclusions:
- Highly charged ions are effective in inducing proton migration in small hydrocarbons.
- The study provides new insights into the fragmentation dynamics of hydrocarbon dications.
- Kinetic energy release measurements allow for the identification of precursor dication states.
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