Three-dimensional quantum mechanical studies of D+H2→HD+H reactive scattering. IV. Cross sections and rate constants with rotationally excited target molecules

The body fixed formulation of the adiabatic distorted wave theory is used to study the reactive collisions of the (D,H2) system. Cross sections are obtained on the ab initio potential surface from the threshold to 0.5 eV in relative translation energy for the case where the target molecule is in the first rotationally excited state. The present results of the ortho-hydrogen are qualitatively similar to but quantitatively different from the previous results of para-hydrogen. The statistically weighted cross sections and product state distributions are found in general agreement with the molecular beam experiment. The reaction rates are obtained by integration over the distribution function. From 150 to 750°K where there are experimental data, the curvature in the Arrhenius plot of the calculated rate constants is in excellent agreement with experiment. However, the absolute magnitudes of the rate constants are smaller than the experimental ones.