PRODUCTION OF ELECTRONICALLY EXCITED FRAGMENTS BY ELECTRON IMPACT DISSOCIATION OF $CH_{4}$, $C_{2}H_{4}$, $CH_{3}OH$ AND ISO - $C_{3}H_{7}OH$

Abstract

The production of electronically excited atomic and diatomic fragments formed by electron impact dissociation of small organic molecules has been observed by monitoring the fluorescence of the excited species. Appearance potentials for emission are generally several volts higher than minimum values calculated from thermodynamic data indicating considerable release of translational energy and/or internal excitation of the fragment (s). In addition, most fragment species exhibit multiple thresholds below 50 eV implying that several dissociation processes contribute significantly to the production of each fragment species at higher energies.