A REVIEW OF CHARGE TRANSFER PROCESSES IN GASES. Geophysical Research Papers No. 48

A review is given of the nature and importance of the charge transfer process (A/sup +/ + B yields A + B/sup +/) particularly with regard to its role in certain chemical and physical processes. Experimental techniques for determining the charge transfer cross sections are discussed, with special reference to the recent method whereby the number of ions due to charge transfer is directly compared with that of the primary beam. This technique has been utilized by the authors. The cross sections obtained from experimental data in the energy range 50 to 800 ev are discussed in some detail. The data obtained by other investigators from thermal energies to 40 kev are also presented. It is shown that the adiabatic theory (Massey) satisfactorily explains the charge transfer reaction for a large number of simple atomic and molecular cases. However, certain very simple cases cannot be explained in terms of this theory even by assuming excited states or dissociation of the molecules by collision. (auth)