A novel route to H2O2+ ions via direct generation of the oxywater cation H2OO+

The oxywater cation H2OO+ was generated in the gas phase by ionization of mixtures containing O3, O2 and H2O. Different ionic mixtures, rich in either the H2OO+ or the HOOH+ isomer, were obtained by O3/O2/H2O–O2/H2O CI, and by CH3OH/O2–CH2O/O2 CI, respectively. The H2O2+ ions were characterized by high-resolution CAD mass spectrometry, and structural and energetic effects were examined.