Chemical reaction in electric discharge. V. Reaction kinetics in a low frequency modulated discharge

Abstract

A current modulation technique has been developed for the determination of kinetic information in glow discharges through flowing gases. A low frequency sinusoidal modulation superimposed on the dc discharge current produces modulations in the electron density and radical concentrations. Measurements of the amplitudes and phase shifts of radical concentrations can be used to elucidate reaction mechanisms and to determine rate constants for some reaction processes.The kinetic response of discharge chemical phenomena to an applied current modulation is discussed for several general types of reaction mechanisms. Rates of O atom production and removal measured in a current modulated O2 glow discharge are compared to rates measured in a dc glow discharge. The excellent agreement of these two sets of results provides an experimental foundation for the current modulation method.