title: Two Spin-State Reactivity in the Activation and Cleavage of CO2 by [ReO2](.).
abstract: The rhenium dioxide anion [ReO2](-) reacts with carbon dioxide in a linear ion trap mass spectrometer to produce [ReO3](-) corresponding to activation and cleavage of a C-O bond. Isotope labeling experiments using [Re(18)O2](-) reveal that (18)O/(16)O scrambling does not occur prior to cleavage of the C-O bond. Density functional theory calculations were performed to examine the mechanism for this oxygen atom abstraction reaction. Because the spins of the ground states are different for the reactant and product ions ((3)[ReO2](-) versus (1)[ReO3](-)), both reaction surfaces were examined in detail and multiple [O2Re-CO2](-) intermediates and transition structures were located and minimum energy crossing points were calculated. The computational results show that the intermediate [O2Re(η(2)-C,O-CO2)](-) species most likely initiates C-O bond activation and cleavage. The stronger binding affinity of CO2 within this species and the greater instabilities of other [O2Re-CO2)](-) intermediates are significant enough that oxygen atom exchange is avoided.
authors.affiliation: School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne , 30 Flemington Road, Parkville, Victoria 3010, Australia.|ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, University of Melbourne , Parkville, Victoria 3010, Australia.|Department of Engineering and Geology (INGEO), "G. d'Annunzio" University of Chieti and Pescara , Viale Pindaro, 42, I-65127 Pescara, Italy.
authors.forename: Valentino
authors.initials: V
authors.lastname: Canale
authors.affiliation: School of Physical Sciences - Chemistry, University of Tasmania , Private Bag 75, Hobart, Tasmania 7001, Australia.
authors.forename: Robert
authors.initials: R
authors.lastname: Robinson
authors.affiliation: School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne , 30 Flemington Road, Parkville, Victoria 3010, Australia.|ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, University of Melbourne , Parkville, Victoria 3010, Australia.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Zavras
authors.affiliation: School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne , 30 Flemington Road, Parkville, Victoria 3010, Australia.|ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, University of Melbourne , Parkville, Victoria 3010, Australia.
authors.forename: George N
authors.initials: GN
authors.lastname: Khairallah
authors.affiliation: Department of Engineering and Geology (INGEO), "G. d'Annunzio" University of Chieti and Pescara , Viale Pindaro, 42, I-65127 Pescara, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: d'Alessandro
authors.affiliation: School of Physical Sciences - Chemistry, University of Tasmania , Private Bag 75, Hobart, Tasmania 7001, Australia.
authors.forename: Brian F
authors.initials: BF
authors.lastname: Yates
authors.affiliation: School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne , 30 Flemington Road, Parkville, Victoria 3010, Australia.|ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, University of Melbourne , Parkville, Victoria 3010, Australia.
authors.forename: Richard A J
authors.initials: RA
authors.lastname: O'Hair