I-I-1 Quantum Dynamics of O(3P) + HCl -> OH + Cl: Effects of Reagent Rotational Excitation

Katsuyuki NOBUSADA, Kengo MORIBAYASHI (NIFS, Nagoya) and Hiroki NAKAMURA

[J. Chem. Soc. Faraday Transactons 93, 721 (1997)]

Accurate quantum dynamics of the chemical reaction O (3P) + HCl (ji, vi=0) -> OH (jf,vf=0) + Cl is studied using the hyperspherical coordinate approach and the Koizumi-Schatz-Gordon (KSG) potential-energy surface. The effects of reagent rotational excitation on the dynamics are investigated. The study considers total energies up to 0.7 eV and reagent rotational states, ji=0-10. The total reaction cross-section shows a strong dependence on ji. This overall trend is enhanced on increasing the total energy. The final rotational state (jf) distributions are also investigated. Interestingly, the distribution shows a peak at high jf(~~ 10) irrespective of ji and the total energy. The qualitative features are quite similar to the experimental results. Finally, the state-resolved rate constant and the thermal rate constant are evaluated. Because of the enhancement of the reaction by the reagent rotational excitation, the state resolved rate constants for 8 ~< ji =< 10 are two or three orders of magnitude larger than those for ji=5. The thermal rate constant obtained is thus much larger than the experimental data implying that the barrier height of the KSG surface may be too low.


back to CONTENTS of Research Activities I