Stereodynamical control of resonances in the Cl + H2 (v=1, j=1) → HCl plus H reaction

The stereodynamical control of resonance profoundly influences the outcomes of molecular collisions. Here, we perform time-dependent wave packet calculations for the Cl + H2 (v = 1, j = 1) -> HCl + H reaction to investigate how stereodynamical control influences reaction resonances. The results of the dynamical calculations indicate that the backward scattering differential cross section of the HCl (v ' = 2) product exhibits two pronounced peaks at collision energies of similar to 0.4 eV and similar to 0.5 eV. Analysis confirms that these characteristic peaks are attributable to reaction resonances. This work explores the impact of different alignment angles of the H2 reactant molecule on these two reaction resonances. It is found that the parallel alignment of the H2 molecule markedly amplifies the intensity of the resonance peaks, while the perpendicular alignment results in a notable suppression of these features. Furthermore, the alignment angle of the reactants significantly influences the scattering direction of the products. Products at the energies of resonances from the head-on collision tend to scatter in the backward direction. In contrast, those from the side-on collision are more likely to scatter forward and sideways.