The kinetics of energetic O$^{\mathrm{-}}$ ions in oxygen discharge plasmas

Monte Carlo simulation was used to study the translational relaxation of energetic O$^{\mathrm{-}}$ ions formed due to dissociative electron attachment to O$_{\mathrm{2}}$ molecules in oxygen and oxygen-containing mixtures in a strong electric field. Initial O$^{\mathrm{-}}$ ions have rather high energies and are more reactive then the ions reaching equilibrium with electric field. Therefore, there is a noticeable probability that electron detachment from the energetic O$^{\mathrm{-}}$ ions or their charge transfer to form O$_{\mathrm{2}}^{\mathrm{-}}$ ions proceed prior to energy degradation of these ions. The probabilities of electron detachment and charge transfer were calculated as a function of the reduced electric field in oxygen and some oxygen-containing mixtures. Comparison with available information about the electron detachment and charge transfer rate coefficients for O$^{\mathrm{-}}$ ions shows that the effect of high reactivity of the initial energetic ions can lead to orders of magnitude increase in the effective rates of these reactions and should be considered in numerical simulation of the properties of discharge plasmas in oxygen and oxygen-containing mixtures.