Theoretical study of the stereodynamics of the reactions of He+H2+/HD+

The vector correlations between products and reagents for the chemical reactions He+H2+/HD+ have been calculated by means of the quasi-classical trajectory (QCT) method at a collision energy of 1.0 eV on the AQUILANTI 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]. The isotope effect on dynamical stereochemistry of the title reactions is discussed in detail. The pronounced isotopic effect may be ascribed to the difference of the mass factor in the two reactions.