This paper investigates the stereodynamics of the reaction He＋HD^＋ by the quasi-classical trajectory （QCT） method using the most accurate AQUILANTI surface [Aquilanti et al 2000 Mol. Phys. 98 1835]. The distribution P（Фτ） of dihedral angle and the distribution P（θτ） of angle between k and j＇ have been presented at three different collision energies. Four generalized polarization-dependent differential cross-sections （2π/σ）（dσ00/dωt）, （2π/σ）（dσ20/dωt）, （2π/σ）（dσ22/dωt）, （（2π/σ）（dσ21-/dωt） are also calculated. Some interesting results are obtained from the comparison of the stereodynamics of the title reaction at different collision energies.
Calculations of He+H2+ (v=l,j=l) reaction system are carded out on a new potential energy surface (PES) at different collision energies with the quasi-classical trajectory (QCT) method. The results of the reaction probability and the cross section curves show an obvious oscillatory structure attributed to the resonances caused by the potential well of the Hell2+ complex. The three angular distributions P(θr), P(φr) and P(θr,(φr) as well as four polarization dependent differential cross sections (PDDCSs) are calculated, respectively. Results indicate that the collision energy has great influence on both the vector correlation of k-k', k-j', k-k'-j' and the PDDCSs of the title reaction. The rotational polarization of product Hell+ presents diverse characteristics at dif- ferent collision energies. The rotational angular momentum vectorsj' of product are both aligned and oriented. Furthermore, the product Hell+ tends to scatter forward correspondingly as the collision energy increases.
