Electron attachment to pentafluorobenzene, to oxygen in a mixture of 90% argon and 10% methane, and to oxygen in various polar/nitrogen mixtures

By means of electron swarm experiments, electron attach-ment to pentafluorobenzene (C₆HF₅) in nitrogen (N₂) and to oxygen (O₂) in various gas mixtures has been studied. variation of the electron attachment rate for C₆HF₅ in N₂ the gas pressure and with the mean electron energy was determined. The lifetime of the species C₆HF^-*₅ against autoionization was deduced and the electron attachment cross section for C₆HF₅ was calculated. The influence of the permanent electric dipole of C₆HF₅ upon the electron attachment process is discussed.

Electron attachment to O₂ in P-10 (90% argon + 10% methane) and in mixtures of various polar molecules with N₂ was investigated. As a preliminary to these studies electron drift velocities in P-10 and in the various mixtures of polar species with N₂ were determined. These drift velocities are reported and discussed. The variation of the electron attachment rate for O₂ in P-10 with the P-10 pressure and the mean electron energy was determined. The attachment rate as a function of mean electron energy was found to possess distinct structure. Models which account for this structure and for the variation of the attachment rate with the P-10 pressure are advanced and the corresponding reaction rate constants are presented. electron attachment rates for O₂ in mixtures of N₂ with 1-butene, dimethyl amine, ammonia, trifluoromethane, and acetaldehyde were measured. Models of the variation of the attachment rate with the concentration of the polar species are advanced and the corresponding reaction rate constants are presented.