Luminescence Measurements of the Hyperthermal Reactions of N⁺/N + NH₃

Chemi-luminescence emitted in the ultraviolet, visible and near infrared from the collision of N⁺ or N with NH₃ at collision energies between 20-300 eV (center of mass) was measured and the energy dependence of the respective emissions quantified in the emission excitation cross sections. For both primary collision species, the strongest features are assigned to emissions from NH (A-X) and the hydrogen Balmer series. Additional features originating from N I and NH (c-a) emissions were also observed. Most of the transitions are consistent with short-range interactions resulting in collision induced dissociation of the NH₃ molecule. It has been found previously that the NH (A-X) cross sections are independent of collision partner in studies with Ar⁺, Kr⁺ and Xe⁺ with NH₃. Reaction with N⁺ largely agrees with these findings, but the cross sections from collisions with neutral N is much reduced.