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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Significant nonadiabatic effects in the C + CH reaction dynamics.
Huan Yang1, Marlies Hankel, Yujun Zheng
1School of Physics, Shandong University, Jinan 250100, China.
The Journal of Chemical Physics
|July 20, 2011
Summary
Quantum nonadiabatic calculations reveal significant effects in the C + CH reaction dynamics. The study provides a state-selected rate constant crucial for interstellar cloud chemical models.
Area of Science:
- Quantum Chemistry
- Chemical Dynamics
- Astrochemistry
Background:
- The C + CH reaction is important in interstellar chemistry.
- Understanding nonadiabatic effects is crucial for accurate reaction dynamics.
Purpose of the Study:
- To perform rigorous quantum nonadiabatic calculations for the C + CH reaction.
- To investigate the reaction dynamics and determine key reaction parameters.
Main Methods:
- Quantum nonadiabatic calculations were performed on coupled electronic states (1(2)A' and 2(2)A').
- Initial wave packet started from the 1(2)A' state with CH in its ground rovibrational state.
- Reaction probabilities calculated for total angular momenta J=0-160 to obtain integral cross sections.
Main Results:
- Significant nonadiabatic effects were observed in the reaction dynamics.
- The branching ratio for C(2) ground and excited states was approximately 0.6.
- A state-selected rate constant k(v=0, j=0) at 300 K was determined to be 2.52 × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹.
Conclusions:
- Nonadiabaticity plays a critical role in the C + CH reaction.
- The calculated rate constant serves as a valuable reference for interstellar chemical models.
- This research enhances our understanding of chemical processes in interstellar clouds.
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