Observation of stable HO sub(4) super(+) and DO sub(4) super(+) ions from ion-molecule reactions in helium nanodroplets

• Published in: Physical chemistry chemical physics : PCCP 2016-05, Vol.18 (19), p.13169-13172
• Main Authors: Renzler, Michael, Ralser, Stefan, Kranabetter, Lorenz, Barwa, Erik, Scheier, Paul, Ellis, Andrew M
• Format: Article
• Language: English
• Subjects: Channels; Clusters; Dimers; Equivalence; Ionization; Liquid helium; Nanostructure; Physical chemistry
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c6cp01895e

Ion-molecule reactions between clusters of H sub(2)/D sub(2) and O sub(2) 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 H sub(3) super(+) or H sub(3) super(+)(H sub(2 )) sub(n) clusters and their deuterated equivalents. Very little HO sub(2) super(+) is seen from the reaction of H sub(3) super(+) with O sub(2), which is attributed to an efficient secondary reaction between HO sub(2) super(+) and H sub(2). On the other hand HO sub(4) super(+) is the most abundant product from the reaction of H sub(3) super(+) with oxygen dimer, (O sub(2)) sub(2). The experimental data suggest that HO sub(4) super(+) is a particularly stable ion and this is consistent with recent theoretical studies of this ion.