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Published on: September 18, 2016
Theoretical study of HCN(+) + C2H2 reaction
Yan Li1, Hui-ling Liu, Xu-ri Huang
1State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, People's Republic of China.
The Journal of Physical Chemistry. A
|August 13, 2008
Summary
This study investigates the ion-molecule reaction between hydrogen cyanide ion (HCN+) and acetylene (C2H2). The reaction primarily forms hydrogenated carbonitride ions (H2C3N+) and hydrogen atoms, indicating a rapid and efficient chemical process.
Area of Science:
- Astrochemistry
- Theoretical Chemistry
- Chemical Kinetics
Background:
- The reaction between hydrogen cyanide ion (HCN+) and acetylene (C2H2) is relevant to interstellar chemistry.
- Understanding ion-molecule reactions is crucial for modeling chemical processes in various environments.
Purpose of the Study:
- To theoretically investigate the reaction pathways and products of HCN+ + C2H2.
- To determine the most abundant and kinetically accessible products of this ion-molecule reaction.
Main Methods:
- High-level computational chemistry methods, including B3LYP/6-311G(d,p) and CCSD(T)/6-311++G(3df,2pd) single-point calculations.
- Exploration of energetically allowed reaction pathways and dissociation products.
Main Results:
- Eight thermodynamically and kinetically accessible dissociation products were identified.
- The most abundant product is H2C3N+ + H (P1).
- Other products like C2H2+ + HCN (P7) and HC3N+ + H2 (P3) are also feasible, with P4-P6 and P8 becoming significant at higher temperatures.
Conclusions:
- The reaction HCN+ + C2H2 is predicted to be rapid due to all intermediates and transition states being energetically lower than the reactants.
- The calculated results align with experimental observations of a large rate constant at room temperature.
- This study provides insights into the reaction mechanism of HCN+ with pi-bonded molecules.
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