DYNAMIC SOLVATION EFFECTS ON SURFACE-IMPACT DISSOCIATION OF I-2(-)(CO2)(N)

Surface-impact dissociation of I-2(-) (CO2)(n) was studied by a molecu lar dynamics simulation in comparison with the experimental results. T he branching fraction, f(dis), of the I-2(-) dissociation was calculat ed as a function of the parent cluster size, n. This computational res ult reproduces the experimental one. We calculated a number of the I-2 (-) dissociation events starting from given initial orientations. The most favorable molecular orientation obtained supports the wedge effec t in which a CO2 molecule located at the waist position of the I-2(-) core ion splits the I-2(-) bond as if a piece of wood is split by a me chanical thrust against a wedge. The time profile of the wedge action calculated for the I-2(-) (CO2) impact shows that more than 20 % of th e collision energy is converted to the vibrational energy of the I-2(- ).