Formation of molecular iodine in high-energy four-center CH₃I+CH₃I collisions

Classical trajectory computations and a kinematic analysis of the collision of two CH₃I molecules are presented. The yield of molecular and atomic iodine is examined as a function of reactant translational and vibrational energy. The potential energy function is of the LEP form, which has a high late barrier where all bonds are extended. Vibrational excitation of CH₃I enhances the barrier crossing and molecular products are formed highly vibrationally excited. Kinematic considerations indicate the same trends. The results are discussed as a possible mechanism for the formation of molecular iodine via ultrafast heating achieved in wall collisions of CH₃I clusters.