Time-dependent quantum dynamics study of the Cl+H-2 reaction

We report rigorous quantum dynamics studies of the Cl+H-2 reaction. The tim e-dependent wave packet calculations are performed on the semiempirical G3 and the new BW2 potential energy surfaces. Initial state-specific total rea ction probabilities and cross sections are calculated and the thermal rate constant is obtained. The quantum dynamics calculations show a striking dif ference in the energy dependence of reaction probabilities between the G3 a nd BW2 surfaces, with the former having a smaller reaction threshold. The c alculated rate constant on the G3 surface is in good agreement with previou s theoretical calculations at room temperature. The calculated rate constan t on the new BW2 surface is smaller than that on the G3 surface, and compar ison of them with experimental measurement is shown. (C) 2000 American Inst itute of Physics. [S0021-9606(00)01028-X].