Stable [C2H7O2]+ isomers: Experimental and theoretical evidence for the existence of protonated peroxides and proton‐bound dimers in the gas phase

Evidence is presented for the gas phase generation of at least eight stable isomeric [C2H7O2]+ ions. These include energy‐rich protonated peroxides (ions {article}{empty}{document}CH₃ CH₂ O O⁺ H₂{document} (e), {article}{empty}{document}CH₃ CH₂ O⁺ (H)OH{document} (f) and {article}{empty}{document}CH₃ O O⁺ (H)CH₃ (g)),{document} (g)), proton‐bound dimers (ions {article}{empty}{document}CH₃ CH = O · · · H³ · · · OH₂{document} (h) and {article}{empty}{document}CH2 = O · · · H⁺ · · · HOCH₃{document} (i)) and hydroxy‐protonated species (ions {article}{empty}{document}CH₂ (OH)CH₂ O⁺ H₂ (a),{document} {article}{empty}{document}CH₃ CH(OH) O⁺ H₂{document} (b) and {article}{empty}{document}CH₃ OCH₂ O⁺ H₂{document} (c)). The important points of the present study are (i) that these ions are prevented by high barriers from facile interconversion and (ii) that both electron‐impact‐ and proton‐induced gas phase decompositions seem to proceed via multistep reactions, some of which eventually result in the formation of proton‐bound dimers.