Detailed quasiclassical dynamics of the F− + SiH3Cl multi-channel reaction

Abstract

We report a detailed quasiclassical trajectory study on the F⁻ + SiH₃Cl multi-channel reaction using a full-dimensional ab initio analytical potential energy surface. Reaction probabilities, cross sections, initial attack and scattering angle distributions as well as product relative translational, internal, vibrational, and rotational energy distributions are obtained in the collision energy range of 1–40 kcal mol⁻¹ for the following channels: SiH₃F + Cl⁻, SiH₂Cl⁻ + HF, SiH₂F⁻ + HCl, SiH₂FCl + H⁻, SiH₂ + FHCl⁻, and SiHFCl⁻ + H₂. All the channels are translationally cold indicating indirect mechanisms, except proton transfer (SiH₂Cl⁻ + HF), which shows mixed direct–indirect character. The angular distributions vary depending on collision energy and inversion/retention for SiH₃F + Cl⁻. In the case of SiH₂Cl⁻ + HF front-side/back-side attack backward–forward/forward scattering preference is found at low/high collision energy. SiH₂F⁻ + HCl is formed with isotropic scattering and the preferred angle of attack is similar to the SiH₃F + Cl⁻ channel. SiH₂FCl + H⁻/SiH₂ + FHCl⁻ favors back-side attack and isotropic/backward scattering, whereas SiHFCl⁻ + H₂ does not show significant angular preference.