Isotope effect of quantum mechanical collinear He+H-2(+) reaction at energies below and above the dissociation threshold

Accurate time-independent quantum mechanical calculations have been carried out for collinear He + XH(+), HX(+), X(2)(+) (X = Mu, H, D, T) collisions on a realistic potential-energy surface at total energies of 1-6 eV. The present paper provides an entire view of the reaction features over a wide range of energies both below and above the dissociation threshold. At energies below the dissociation threshold, the resonance structure seen in the exchange reaction is studied for the isotope combinations mentioned above. At energies above the dissociation threshold, the effect of isotope variations on the competition between the exchange and dissociation reactions is discussed.