Isotopic Effects on Stereodynamics of the C⁺ + H₂ → CH⁺ + H Reaction

The effects of isotope substitution on stereodynamic properties for the reactions $C^{+}+H_2/HD/HT\to {CH}^{+}+H/D/T$ have been studied applying a quasi classical trajectory method occurring on the new ground state ${CH}_2^{+}$ potential energy surface [J. Chem. Phys. 142 (2015) 124302]. In the center of mass coordinates applying the quasi classical trajectory method to investigate the orientation and the alignment of the product molecule. Differential cross section and three angle distribution functions P(θ_r), P(ϕ_r), P( ${\theta }_r,{\varphi }_r$ ) on the potential energy surface that fixed the collision energy with a value is 40 kcal/mol have been studied. The isotope effect becomes more and more important with the reagent molecules H ₂ changing into HD and HT. P(${\theta }_r,{\varphi }_r$) as the joint probability density function of both polar angles θ _r and ϕ _r, which can illustrate more detailed dynamics information. The isotope effect is obvious influence on the properties of stereodynamics in the reactions of $C^{+}+H_2/HD/HT\to {CH}^{+}+H/D/T$. (paper)