Appearance Potentials of the Fragment Ions from CF3I

Abstract

The ionization‐efficiency curves for the parent and fragment ions from CF₃I have been examined using Morrison's second differential method. Accurate appearance potentials can be obtained only for some ions, i.e., CF₃I⁺=10.5±0.1 eV, CF₃⁺=11.5±0.1 eV, and I⁺=13.4±0.1 eV, but not for the ions CF₂I⁺, CF₂⁺, and CF⁺ by this or any other method. The kinetic energy of the fragment ions near their threshold has been determined using a retardation method.