Atomic and Molecular Photoelectron Angular Distributions Measured near Threshold

The differential angular distributions of photoelectrons emitted in the formation of various ionic states have been determined for Ar, Kr, Xe, H₂, N₂, and O₂. Where possible several photon energies have been employed, the 21.21‐eV He resonance line and the 16.67‐ and 16.85‐eV Ne resonance doublet. In most cases the angular dependence for the photoelectron emission can be described by a function of the form ${\text{1\hspace{0.17em}+\hspace{0.17em}βP}}_2(\cos \mathrm{\Theta )}$ . For certain of the rare gases ionized by the Ne resonance doublet large deviations from this prediction were obtained. These deviations are related to the energy of the outgoing electron and the structure of the ionic species formed.