Dissociative electron attachment cross sections for halofluoromethanes

Abstract

Dissociative electron attachment cross sections for the halofluoromethanes, CF3X and CF2X2 (X=Cl, Br, I), have been measured for electron energies less than 6 eV under single-collision conditions at temperatures of 393 and 563 K. Peaks in the cross sections as a function of electron energy are observed near threshold and in the vicinity of previously-identified negative ion resonances. The magnitude of the threshold enhancement depends on the nature of the halogen substituent. Changes with temperature include a slight increase in the cross section at threshold and a broadening of the peaks below 1 eV.