Approximate scaling formula for ion–ion mutual neutralization rates

A complex potential model is used to treat the mutual neutralization of positive and negative ions. The model is used to examine neutralization by the charge transfer mechanism and also by internal excitation leading to capture. It is found that electron transfer is the dominant process for simple ions and small hydrated ions. The numerical results of the theory have been parameterized in terms of the reduced mass of the collision and the electron affinity of the electron donor. This procedure yields an approximate scaling formula that fits a wide range of experimental data to an accuracy of about ±30%.