Cross Sections for Charge Transfer Collisions of Low-Energy Ions in N2 and O2

Abstract

Measurements have been made of the cross sections for charge transfer collisions between the low-energy (9—250 ev) ions, N2+, O2+, O+ and N+, and the molecules N2 and O2. Two reactions (N+, N2; O+, N2) have been reported by other workers and are compared with present work. The experimental method utilizes a radio-frequency mass spectrometer as an ion source. The ions are collimated and enter a weak radial electric field of cylindrical symmetry. The secondary ions are separated from the primary beam and the ratio of the two currents is measured as a function of pressure. Results are discussed in terms of the adiabatic collision condition and possible internal energy states of the ions and molecules.