Isotopic effect on stereodynamics of the reactions of HÂ +Â HeH+/HÂ +Â HeD+/HÂ +Â HeT+

The vector correlations in the H + HeH+/H + HeD+/H + HeT+ reactions have been investigated by the means of quasi-classical trajectory calculations on a new potential energy surface [C.N. Ramachandran, D. De Fazio, S. Cavalli, F. Tarantelli, V. Aquilanti, Chem. Phys. Lett. 469 (2009) 26-30] constructed by the means of full configuration interaction. The distributions of P(θr), P(ϕr) and the PDDCSs of (2π/σ)(dσ00/dwt), (2π/σ)(dσ20/dwt), (2π/σ)(dσ22+/dwt) have been calculated based on the surface. The remarkable isotopic effect is revealed and we explored at length the reasons which consist in the different mass factors and different effective potential energy wells in the three reactions. Furthermore, we compare some of the results mentioned above with the corresponding ones studied on a notable surface [P. Palmieri, C. Puzzarini, V. Aquilanti, G. Capecchi, S. Cavalli, D. De Fazio, A. Aguilar, X. Gimenez, J.M. Lucas, Mol. Phys. 98 (2000) 1835] and find primary agreements, which validates the usefulness of the new potential energy surface for dynamical calculations.