Modeling of ion molecule reactions at high pressures

Recent modeling of ion molecule reactions has suggested that the dynamics of the complex formed from the initial encounter between the reactants may control the overall rate at which the products appear. At atmospheric pressures both coherent and incoherent collisional processes of excitation and deexcitation of the complex contribute substantially to the yield of products. A phenomenology is predicted that largely agrees with observations of termolecular rate coefficients for ion molecule reactions in the 10(-28) to 10(-30) cm6sec-1 range. Primary variables are the dependence of the energy transfer function upon parameters describing collisions with the complex and the approximate geometric shape of the complex