Anion velocity imaging study of the dissociative electron attachment to CFCl3

Abstract

Time-sliced velocity imaging experiments have been performed for the low-energy electron dissociative attachment to CFCl${}_{3}$ in the gas phase. The time-sliced velocity images of the F${}^{\ensuremath{-}}$ anionic fragment, recorded at different electron attachment energies (2.0--7.0 eV), indicate image pattern evolutions. The angular and kinetic energy distributions of the F${}^{\ensuremath{-}}$ fragment are interpreted with two shape-resonant states of CFCl${}_{3}$${}^{\ensuremath{-}}$ and thermochemistry calculations for dissociation thresholds. The dramatic reduction of the F${}^{\ensuremath{-}}$ kinetic energy observed at higher attachment energies is possibly due to two-body dissociation with an electronically excited state of CCl${}_{3}$ (${}^{2}{A}^{\ensuremath{'}\ensuremath{'}}$) or three-body dissociations.