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Abstract
This dissertation presents an electron beam study of the dissociative attachment process in the chloromethanes. A novel design of a high sensitivity ion counting system was incorporated in this work.
Each chloromethane displays two peaks in the dissociative attachment cross section below an electron energy of 1 eV, with the first peak consistently at zero energy and the second peak ranging from 0.27 to 0.80 eV. A systematic increase of the dissociative attachment cross sections is observed each time a $Cl$ atom replaces an $H$ atom. The ratio of the cross sections near zero electron energy between the highest and lowest attachers, namely $CCl\sb4$ and $CH\sb{3}Cl$ respectively, is approximately six orders of magnitude, consistent with the earlier swarm measurements.
Also included in this dissertation is the application of the dissociative attachment process to study gas-surface vibrational energy exchange. In this work, cool gas was allowed to flow through a heated tube and then intercepted by the electron beam at right angles. $N\sb{2}O$ was used in this study because its dissociative attachment cross section is very sensitive to temperature, permitting us to use it as a diagnostic tool for the measurement of vibrational temperature.
