LOW-ENERGY-ELECTRON ATTACHMENT TO BROMINATED ETHANES AND ETHYLENES

Rate constants have been measured for electron attachment to CHBr2CHBr 2, CHBr2CH2Br, CHBr2CH3, CH2BrCH2Br, CF2BrCH2Br, CF2BrCF2Br, CF3CH2Br, CH2BrCH2F, CHBrCBr2, and CHBrCHBr in Xe buffer gas at room temperatur e with mean electron energies between 0.04 and 2 eV using the pulse-ra diolysis microwave-cavity method combined with microwave heating. The rate constant as a function of the mean electron energy is converted t o a cross-section as a function of electron energy by an unfolding pro cedure. In all the compounds, the derived cross-sections show a peak a t 0 eV with no other peaks at higher energies. The effects of molecula r structure on the attachment processes are discussed.