The rates of formation of negative ions for some halocarbons in nitrogen and in argon-nitrogen mixtures in dependence on the mean electron energy

An experimental electron swarm method with a special electron capture detector arrangement is described which allows one to modify the energy of low energetic electrons from thermal to 2.8 eV by means of radio-frequency voltage. Using theoretically calculated values of electron energy distribution functions in nitrogen and argon the attachment coefficients and the formation rates of negative ions for chlorobenzene, benzyl chloride, chloroform, methylene chloride, nitrobenzene, propyl iodide, trichloroethylene and carbon disulfide were determined in dependence on the mean electron energy. Mean electron attachment cross sections could be estimated. (author)