COVARIANCE-MATRIX MASS-SPECTRAL MAPS OF POLAR DISSOCIATION CHANNELS IN CF4

Covariance matrix mass spectra of positive and negative ions ejected b y polar dissociating states excited by electron impact on CF4 are repo rted for impact energies from 18.7 to 43.7 eV. This is the first examp le of covariance matrix mass spectral maps of polar dissociation. Evid ence for the reaction products CF3+ + F-, CF2+ + F- + F, CF+ + F- + p, and F+ + F- + p, where p stands for neutral species, were found. The ion translational energies are cold relative to those observed for pos itive ion-positive ion dissociation channels. The CF2+ + F- channel wa s observed to be the weakest and the only negative ion observed is F-. Absolute cross section values are estimated.