Translational energy dependence of the Rb+CH3I reaction cross section: Evidence for a minimum near 0.9 eV

The present study is a detailed reinvestigation of the crossed-beam reaction Rb+CH3I→RbI+CH3 over the translational energy range 0.5–1.7 eV. The integrated reaction cross section σR decreases with energy reaching a minimum near 0.9 eV, then rises slightly as the energy is increased further. This confirms the tentative conclusion regarding the existence of a minimum in σR(E) advanced by Litvak, Ure?a, and Bernstein [J. Chem. Phys. 61, 4091 (1974)] on the basis of less extensive data. A comparison is made of the overall body of experimental results with four different theoretically predicted σR(E) dependencies from the literature.