VIBRATIONAL PRODUCT STATE DYNAMICS IN SOLUTION-PHASE BIMOLECULAR REACTIONS - TRANSIENT INFRARED STUDY OF CN RADICAL REACTIONS

Solution phase bimolecular reactions of the CN radical are observed us ing transient infrared methods. Photolysis of ICN in chloroform produc es CN radicals that react after thermalization to form HCN and CICN as products. In the deuterated solvent, some of the nascent DCN molecule s are formed in a vibrationally excited level. This constitutes the fi rst observation of vibrationally excited products subsequent to a bimo lecular reaction in solution. Temperature-dependent measurements indic ate that the barrier to reaction is low but that solvent friction is i mportant in the reaction. The observed product state energy partitioni ng and slow reaction rates indicate that the dynamics of reactive barr ier crossings are significantly altered upon solvation.