Recombination and Ion-Conversion Processes of Argon Ions

The properties of ${\mathrm{Ar}}^{+}$ and ${\mathrm{Ar}}_2^{+}$ were studied in helium-argon mixtures by means of the afterglow method. The time dependence of the number density of these ions was measured by massspectrometric techniques. The temporal behavior of the intensity of various spectral lines was also determined. The studies established the occurrence of the collisional recombination process ${\mathrm{Ar}}^{+}+2e\to \mathrm{Ar}+e+h\nu$, while they confirmed the importance of the dissociative recombination process ${\mathrm{Ar}}_2^{+}+e\to \mathrm{Ar}+\mathrm{Ar}+h\nu$. The collisional process appeared to populate all levels studied, while the dissociative process selectively populated the $2p$ and $3p$ energy levels. The only ion-molecule—association reaction observed for argon concentrations between 0.01 and 5% was ${\mathrm{Ar}}^{+}$+Ar+He→${\mathrm{Ar}}_2^{+}$+He. The rate constant was found to be 8.0×${10}^{-32\mathrm{}}$ ${\mathrm{cm}}^6$ ${\sec }^{-1\mathrm{}}$. The value of the mobility of ${\mathrm{Ar}}^{+}$ in the helium-argon mixtures obeyed Blanc's Law.