Condensed-phase effects on absolute cross sections for dissociative electron attachment to CFCs and HCFCs adsorbed on Kr

Abstract

We present measurements of absolute dissociative electron attachment (DEA) cross sections to CFCl3, CHF2Cl, and CH3CF2Cl adsorbed on the surface of Kr as a function of electron energy (0–10 eV). The DEA cross sections are measured to be ∼7.2×10−15 cm2 at ∼0 eV, ∼4.2×10−16 cm2 at 0.65 eV, and ∼7.8×10−16 cm2 at 0.89 eV for CFCl3, CHF2Cl, and CH3CF2Cl, respectively. This cross section is similar to the gas-phase value for CFCl3, while for the latter two molecules, it is orders of magnitude higher than the gaseous values. These results can be explained by considering the changes in the survival probability of the anion resonance and in the electron capture probability due to the decrease of the nuclear wave function overlap in the Franck–Condon region.