Ion–Molecule Reactions of Oxygenated Species. Proton–Transfer Reactions Involving CHO+

The ionic reactions of the major ions in the mass spectra of formaldehyde, acetaldehyde, ethylene oxide, dimethyl ether, vinyl formate, and formaldehyde–D₂O mixtures have been studied and rate constants determined for ions of 2.4‐eV exit energy. The major reaction involves formation of the protonated molecule. The rate constants for transfer of a proton from CHO⁺ to a neutral molecule M vary from 1.28 × 10⁻⁹ cm³ molecule⁻¹·sec⁻¹ ${\mathrm{(M\hspace{0.17em}=\hspace{0.17em}D}}_2\mathrm{O)}$ to 2.7 × 10⁻⁹ cm³ molecule⁻¹·sec⁻¹ (M = vinyl formate). The rate constants are shown to be in reasonable agreement with theoretical predictions.