title: Is collision-induced dissociation of low-energy carbonyl sulfide cations adversely affected by asymmetry?
abstract: We have measured relative abundances of fragment ions resulting from collision-induced dissociation of OCS(+) ions in collision with xenon neutrals as a function of ion kinetic energy and scattering angle. The lowest energy dissociation product, S(+), dominates at all energies up to 53 eV kinetic energy studied here. Surprisingly, the second most abundant dissociation channel is CS(+) and not CO(+) even though the thermochemical threshold for CO(+) is lower than that for CS(+) and CO(+) is more abundant than CS(+) in the normal mass spectrum of OCS. We do not observe any significant abundance of CO(+) in this energy range, suggesting that collision-induced excitation and dissociation of OCS(+) is significantly different to that of symmetric triatomic ions. A possible role of asymmetry in the molecular ion's collisional activation via neutral collision is suggested for the different behavior.
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA. anil.shukla@pnl.gov
authors.forename: Anil K
authors.initials: AK
authors.lastname: Shukla