Transport properties of mass-identified ions in oxygen, nitrogen, carbon dioxide and carbon monoxide

The interpretation of electrical-discharge phenomena in gases requires detailed information about the transport properties of the ions and electrons involved and about the ion-molecule chemistry in which the ions participate. This paper is devoted to an account of a recent study of ion-transport properties, and in particular gives details of measurements of the lateral diffusion of mass-identified ions in oxygen, nitrogen, carbon monoxide and carbon dioxide. Both positive and negative ions have been examined in a drift-tube system, using a quadrupole mass spectrometer as an integral part of the current-measuring system. The diffusion data obtained are discussed in terms of available theoretical models of ion transport under prebreakdown conditions, and may assist the modelling of typical discharge situations.