Equilibrium Constant and Rates for the Reversible Reaction N4+ ⇆ N2+ + N2

Abstract

The equilibrium currents of ${\mathrm{N}}_4^{+}$ and ${\mathrm{N}}_2^{+}$ in the reaction ${\mathrm{N}}_4^{+}$ ⇆ ${\mathrm{N}}_2^{+}$+${\mathrm{N}}_2$ have been measured as a function of $\frac{E}{p_0}$, the ratio of electric-field strength to pressure, a quantity which is convertible to equivalent ion temperature. The range of $\frac{E}{p_0}$ is from 40 to 70 V ${\mathrm{}\left(\mathrm{cm}\mathrm{Torr}\right)\mathrm{}}^{-1\mathrm{}}$, a range in which the equilibrium of the reaction shifts strongly from the left toward the right. Both the forward and the backward rate constants were also measured. Values are given as a function of $\frac{E}{p_0}$. The range of $p_0$ is from 0.63 to 1.24 Torr but comparisons are also made with older data at 15 to 35 Torr. The ratio of currents of ${\mathrm{N}}_4^{+}$ and ${\mathrm{N}}_2^{+}$ is shown to depend on pressure as predicted from earlier thermodynamic studies.