Ion-Molecule Reactions in Silane

The reactions of primary ions Si⁺, SiH⁺, ${\mathrm{SiH}}_2^{+},$ and ${\mathrm{SiH}}_3^{+}$ with SiH₄ are observed and reported, along with relative and absolute rate constants for the reactions observed. ${\mathrm{SiH}}_2^{+}$ and ${\mathrm{SiH}}_3^{+}$ are seen to undergo H⁻ transfer reactions with large rate constants. All of the ions also participate in reactions yielding higher molecular weight ions containing two silicon atoms. The rate constants for many of these reactions are also large and suggest that the production of higher silanes from silane in activated systems (discharges, nuclear recoil experiments, etc.) may be due in part to the production of these ions.