EFFECT OF LOCATION OF ENERGY BARRIER ON THE PRODUCT ALIGNMENT OF REACTION A+BC

The trajectory calculations of heavy heavy-light, light light-light, h eavy light-light, and light heavy-light mass combination reactions on attractive and repulsive potential surfaces have been carried out to s tudy the dependence of the product rotational alignment on collision e nergies; The calculated results for heavy heavy-light mass combination reaction are compared with the predictions from the constrained produ ct orbital angular momentum model. The final rotational angular moment um was found to be perpendicularly polarized with respect to the reage nts' relative velocity vector on either attractive or repulsive potent ial surface. There is similar behavior of the product rotational align ments as a function of collision energies for heavy heavy-light and he avy light-light reactions, i.e., the more anisotropic the distribution of the product rotational angular momentum vector is, the higher the collision energies are, whether the potential surface is attractive or repulsive. However, the calculations for light light-light mass combi nation reaction predict that the product rotational alignments depend strongly on collision energies for an attractive potential surface, bu t this behavior is not observed on the repulsive potential surface. Fo r light heavy-light mass combination, the product rotational alignment s hardly depend on collision energies on both potential surfaces. (C) 1996 American Institute of Physics.