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Multiple-electron removal from and molecular fragmentation of carbon monoxide molecules caused by collisions with 1-MeV/amu F + ions were studied using the coincidence time-of-Aight technique. In these collisions, multiple-electron removal of the target molecule is a dominant process. Cross sections for the different levels of ionization of the CO molecule during the collision were determined. The relative cross sections of ionization decrease with increasing number of electrons removed in a similar way as seen in atomic targets. This behavior is in agreement with a two-step mechanism, where erst the molecule is ionized by a Franck-Condon ionization and then the molecular ion dissociates. Most of the highly charged intermediate states of the molecule dissociate rapidly. Only CO+ and CO + molecular ions have been seen to survive long enough to be detected as molecular ions. The relative cross sections for the different breakup channels were evaluated for collisions in which the molecule broke into two charged fragments as mell as for collisions where only a single charged molecular ion or fragment were produced. The average charge state of each fragment resulting from CO~+~C'++0'+ breakup increases with the number of electrons removed from the molecule approximately following the relationship i = j=g/2 as long as K-shell electrons are not removed. This does not mean that the charge-state distribution is exactly symmetric, as, in general, removing electrons from the carbon fragment is slightly more likely than removing electrons from the oxygen due to the difference in binding energy. The cross sections for molecular breakup into a charged fragment and a neutral fragment drop rapidly with an increasing number of electrons removed.PACS number(s): 34.50.s, 35.80.+ s, 34.90.+ q

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Application of the dressed-bound-state molecular strong-field approximation to above-threshold ionization of heteronuclear molecules: NO vs. CO J. Chem. Phys. 137, 134307 (2012) Nanoparticle collisions in the gas phase in the presence of singular contact potentials J. Chem. Phys. 137, 064316 (2012) Merged-beams for slow molecular collision experiments J. Chem. Phys. 137, 054202 (2012) Mass-analyzed threshold ionization of an excited state of lanthanum dioxide J. Chem. Phys. 137, 034307 (2012) Non-adiabatic transitions from I2(E0g+ and D0u+) states induced by collisions with M = I2(X0g+) and H2O ABSTRACTThe fragmentation of CO caused by 1 MeV/amu F 4+ impact has been studied using the coincidence time-of-flight technique. The kinetic energy distribution for C + § O + was determined using an extension of a method suggested by Sch~er ei al 1 . This distribution is compared to the Ar la+ impact data of Sampoll ei al. 2 and to photoionization measurements done by Lablanquie e~ a/3. The kinetic energy distribution shifts toward higher energy for 2.4 MeV/amu Ar 14+ impact, indicating that higher excited states of the intermediate C02+ molecular ion are populated in this collision in comparison with the F a+ impact and photodissociation.