Electron–ion recombination rate constants in gaseous, liquid, and solid argon Available to Purchase

Electron drift mobilities μ_e and electron–ion recombination rate constants k_r in gaseous, liquid, and solid argon have been measured by the analysis of transient current induced with the irradiation of an x‐ray pulse as functions of temperature and external electric field strength except solid. The effect of external dc electric field on k_r up to ∼3×10⁻³ Td (1 Td=10⁻¹⁷ V cm²/molecule) was examined in gaseous and liquid phases. The observed k_r values in both liquid and gas phases were found to be much smaller than those calculated by the reduced Debye equation. The deviation, which is bigger in gas than in liquid, has been compared with recent theoretical studies^1–5 which were presented to explain our previous data on the k_r values for methane.⁶ It has been concluded that the recombination also in liquid and gaseous argon is not a usual diffusion‐controlled reaction. In the solid phase the observed k_r values were almost in agreement with those calculated by the reduced Debye equation. The electron–ion recombination rate constants in both liquid and gas phases increased almost linearly with an external dc electric field up to a critical electric field strength below which electron mobility was nearly constant, and decreased with further increase in the electric field where electron mobility also decreased.