Charge inversion and neutralization–reionization mass spectra of some alkoxide ions

Abstract

AbstractThe charge inversion mass spectra of C1 to C3 alkoxide ions have been obtained using He, N2 and O2 as collision gases. The three collision gases show similar efficiencies for collisional charge inversion and produce similar mass spectra, although fewer high‐energy oxenium ions are formed when O2 and N2 are used as collision gases. Using two collision cells and an intermediate deflector electrode the alkoxide ions have been neutralized in the first collision cell and the fast neutrals ionized in the second cell. The neutralization–reionization mass spectra obtained are similar to the direct charge‐inversion mass spectra indicating that mainly alkoxyl radicals are produced, although, depending on the neutralization collision gas and the alkoxide ion studied, other neutrals are formed in small yields. Deuterium isotopic labelling has been used to show that the main fragmentation reactions of the unstable oxenium ions formed involve 1,1‐elimination of H2 or an alkane.