title: Observation of stable HO4(+) and DO4(+) ions from ion-molecule reactions in helium nanodroplets.
abstract: Ion-molecule reactions between clusters of H2/D2 and O2 in liquid helium nanodroplets were initiated by electron-induced ionization (at 70 eV). Reaction products were detected by mass spectrometry and can be explained by a primary reaction channel involving proton transfer from H3(+) or H3(+)(H2)n clusters and their deuterated equivalents. Very little HO2(+) is seen from the reaction of H3(+) with O2, which is attributed to an efficient secondary reaction between HO2(+) and H2. On the other hand HO4(+) is the most abundant product from the reaction of H3(+) with oxygen dimer, (O2)2. The experimental data suggest that HO4(+) is a particularly stable ion and this is consistent with recent theoretical studies of this ion.
authors.affiliation: Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria. Paul.Scheier@uibk.ac.at.
authors.forename: Michael
authors.initials: M
authors.lastname: Renzler
authors.forename: Stefan
authors.initials: S
authors.lastname: Ralser
authors.forename: Lorenz
authors.initials: L
authors.lastname: Kranabetter
authors.forename: Erik
authors.initials: E
authors.lastname: Barwa
authors.forename: Paul
authors.initials: P
authors.lastname: Scheier
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Ellis