Preliminary report on electron energy-loss measurements for CCl3, CCl2F2, CCl3F

Currently, nation-wide research efforts are devoted to studying the possible ozone (O3) depletion in the stratosphere by the chemical action of chlorine atoms released from CCl2F2 or CCl3F upon absorption of ultraviolet radiation. Since electron-impact data taken in the forward scattering direction can be used to derive oscillator strengths and thus to yield apparent photoabsorption cross sections, such an analysis for CCl2F2, CCLl3F, and CClF3 was carried out. Oscillator-strength distributions were obtained between 5 and 20 eV and are compared to available photoabsorption data. Certain photoabsorption values agree very well with these electron-impact data, but other optical studies deviate in some spectral regions by as much as a factor of 5. Also, the electron energy-loss spectrum reveals electronic transitions previously undetected by photoabsorption