An Eight-Degree-of-Freedom, Time-Dependent Quantum Dynamics Study for the H₂+C₂H Reaction on a New Modified potential Energy Surface
An eight dimensional time-dependent quantum dynamics wavepacket approach is performed for the study of the H₂+C₂H ! H + C₂H₂ reaction system on a new modified potential energy surface (PES) [Chem. Phys. Lett. 409, 249 (2005)]. This new potential energy surface is obtained by modifying Wang and Bowman's old PES [ J. Chem. Phys. 101, 8646 (1994)] based on the new ab initio calculation. This new modified PES has a much lower transition state barrier height at 2.29 kcal/mol than Wang and Bowman's old PES at 4.3 kcal/mol. This study shows the reactivity for this diatom-triatom reaction system is enchanced by vibrational excitations of H₂; whereas, the vibrational excitations of C₂H only have a small effect on the reactivity. Furthermore, the bending excitations of C₂H, comparing to the ground state reaction probability, hinder the reactivity. The comparison of the rate constant between this calculation and experimental results agree with each other very well. This comparison indicates that the new modified PES corrects the large barrier height problem in Wang and Bowman's old PES.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 921834
- Report Number(s):
- PNNL-SA-56541; JCPSA6; KP1303000; TRN: US200802%%926
- Journal Information:
- Journal of Chemical Physics, 127(15):Art. No. 154304, Vol. 127, Issue 15; ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
Similar Records
Eight-dimensional quantum reaction rate calculations for the H+CH{sub 4} and H{sub 2}+CH{sub 3} reactions on recent potential energy surfaces
A quantum reaction dynamics study of the translational, vibrational, and rotational motion effects on the HD +H{sub 3}{sup +} reaction