Classical trajectory study of the K + CH₃i reaction

Classical trajectory calculations have been carried out in an attempt to simulate the reactive scattering of K by RI (R = CH3). Several semiempirical three-body potential surfaces have been explored. An electron-jump surface of the covalent-ionic type, with considerable "repulsive energy release," accounts for most of the gross features of the scattering behavior. In particular, it has provided an understanding of the maximum in the reactive cross section <rR(E) for the exchange reaction, which can be attributed to recrossing from the ionic to the covalent region of the potential. The present calculations also predict the onset (above 2.5 eV) of collision-induced dissociation (CID), and show the conservation of total reaction cross section as CID takes over from the exchange reaction.