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16:11
Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Modeling the electron-impact dissociation of methane
Marcin Ziółkowski1, Anna Vikár, Maricris Lodriguito Mayes
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
The Journal of Chemical Physics
|December 20, 2012
Summary
Electron-impact dissociation of methane primarily yields CH(3) fragments. This study used R-matrix theory and trajectory surface hopping to analyze methane
Area of Science:
- Chemical Physics
- Theoretical Chemistry
- Quantum Mechanics
Background:
- Electron-impact dissociation is a key process in plasma chemistry and atmospheric science.
- Understanding methane dissociation pathways is crucial for various applications.
Purpose of the Study:
- To investigate the product yield and branching ratios of electron-impact dissociation of methane.
- To elucidate the dissociation mechanisms of excited methane states.
Main Methods:
- R-matrix theory for electron-methane collisional excitation cross sections.
- High-level electronic structure calculations for excited states.
- Trajectory surface hopping (TSH) for dissociation dynamics.
Main Results:
- Electron impact preferentially excites triplet states of methane.
- TSH calculations reveal cascading to lower excited states before dissociation.
- Singlet dissociation yields CH(2) and CH(3); triplet dissociation yields CH(3) exclusively.
Conclusions:
- Methane dissociation is dominated by CH(3) formation.
- A small yield of CH fragments is also predicted.
- Theoretical insights into methane dissociation dynamics were provided.
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