Ionic Collision Processes in Gaseous N2O

Ionic collision processes have been studied in N₂O by mass spectrometric techniques with particular emphasis on the state of excitation of the N₂O⁺ ion. Evidence is presented for the contention that electrons of energies ≥17 eV on collision with N₂O molecules produce long‐lived excited N₂O⁺ ions which are capable of the reactions $$\begin{array}{c}{\mathrm{N}}_2{\mathrm{O}}^{+}+{\mathrm{N}}_2\mathrm{O}\to {\mathrm{NO}}^{+}+\mathrm{N}+{\mathrm{N}}_2\mathrm{O},\end{array}\begin{array}{c}{\mathrm{N}}_2{\mathrm{O}}^{+}+{\mathrm{N}}_2\mathrm{O}\to {\mathrm{O}}^{+}+{\mathrm{N}}_2+{\mathrm{N}}_2\mathrm{O}\end{array}$$ without significant conversion of translational to internal energy. For electrons with energy ≥17 eV at least 1% of the N₂O⁺ ions appear to have internal energy ≥2.4 eV. It is well known that excited N₂O⁺ ions are involved in the unimolecular predissociation ${\mathrm{N}}_2{\mathrm{O}}^{+}\to {\mathrm{NO}}^{+}+\mathrm{N}$ . However the abundance of these ions which survive for times appropriate to the collision experiments described here is only about 0.01%. In collision of Ar⁺ or ${\mathrm{N}}_2^{+}$ with N₂O simple charge transfer predominates over dissociative reactions even though sufficient energy is available for dissociation to occur.