Charge Transfer Reactions Producing Intrinsic Chemical Change: Methyl, Methylene, and Hydrogen Radicals Produced from Argon and Methane Reactions

Abstract

Charge transfer reactions producing intrinsic chemical changes in the neutral molecule have been proven by mass spectrometric techniques. The charge transfer reaction Ar++CH4→Ar+CH3++Hproducing an intrinsic chemical change in CH4 was found to be more probable by a factor of five than the simple charge transfer reaction Ar++CH4→Ar+CH4+.Charge transfer reactions in mixtures of Ar and CH4 and Kr+CH4 were studied over the pressure range of 0.1–0.5 mm of Hg in the ionization chamber. Reactions were elucidated by catalytic and negative ion studies as well as by the usual pressure and appearance potential techniques. In the Kr+CH4 mixture, the reaction Kr++CH4→Kr+CH3++Hproducing the charged radical CH3+ was found to have a high probability. Absolute values for rate constants and cross sections are given for all of the charge transfer reactions observed in the Ar+CH4 mixture. Products from these elementary charge transfer reactions are correlated to previously reported radiolytic, α ionization (W value), and hydride ion transfer studies.