A quantum mechanical study of dissociative He+H2 collisions Original Research Article

Accurate quantum mechanical calculations are made for a dissociative He + H2 collision on a realistic potential energy surface by using the discrete-variable-representation (DVR) method of Sakimoto and Onda (J. Chem. Phys. 100 (1994) 1171). The molecular orientation (angle γ) relative to the intermolecular (He-H2) axis is frozen in the calculation, and the molecular-orientation dependence of the dissociation is investigated by changing the angle as γ=0 (collinear), π/4, and π/2 (T-shape). It is found that the dissociation probability is strongly dependent on the molecular orientation, and the molecule dissociates more frequently in the T-shape configuration rather than in the collinear one. Furthermore, the dissociation probabilities are compared with the results obtained by the standard close coupling (CC) method for the T-shape configuration (Nobusada et al., Chem. Phys. Letters 233 (1995) 399). The DVR method can provide accurate dissociation probabilities even in the case that convergence has not been fully achieved in the previous CC study.