Translational Energy Effects in the Excited Ca(1D2) + HCl → CaCl(A) + H Reaction. Experiments and a Harpooning Mechanism

Abstract

By using the time-of-flight technique under crossed-beam conditions, the collision energy dependence of the Ca(1D) + HCl → CaCl(A) + H reaction cross-section has been measured over the 0.2−0.5 eV collision energy range and found to have a broad peak at 0.3 eV. An empirical description of entrance covalent channelsincluding orbital alignment effects due to the open-shell nature of calcium atomsand a harpooning mechanism, involving ionic charge-transfer states, account for the observed translational energy dependence of the reaction cross section.