title: Metastable anions of dinitrobenzene: resonances for electron attachment and kinetic energy release.
abstract: Attachment of free, low-energy electrons to dinitrobenzene (DNB) in the gas phase leads to DNB(-) as well as several fragment anions. DNB(-), (DNB-H)(-), (DNB-NO)(-), (DNB-2NO)(-), and (DNB-NO(2))(-) are found to undergo metastable (unimolecular) dissociation. A rich pattern of resonances in the yield of these metastable reactions versus electron energy is observed; some resonances are highly isomer-specific. Most metastable reactions are accompanied by large average kinetic energy releases (KER) that range from 0.5 to 1.32 eV, typical of complex rearrangement reactions, but (1,3-DNB-H)(-) features a resonance with a KER of only 0.06 eV for loss of NO. (1,3-DNB-NO)(-) offers a rare example of a sequential metastable reaction, namely, loss of NO followed by loss of CO to yield C(5)H(4)O(-) with a large KER of 1.32 eV. The G4(MP2) method is applied to compute adiabatic electron affinities and reaction energies for several of the observed metastable channels.
authors.affiliation: Institut für Ionenphysik und Angewandte Physik and Center for Molecular Biosciences Innsbruck, Leopold Franzens Universität, 6020 Innsbruck, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Mauracher
authors.forename: S
authors.initials: S
authors.lastname: Denifl
authors.forename: A
authors.initials: A
authors.lastname: Edtbauer
authors.forename: M
authors.initials: M
authors.lastname: Hager
authors.forename: M
authors.initials: M
authors.lastname: Probst
authors.forename: O
authors.initials: O
authors.lastname: Echt
authors.forename: T D
authors.initials: TD
authors.lastname: Märk
authors.forename: P
authors.initials: P
authors.lastname: Scheier
authors.forename: T A
authors.initials: TA
authors.lastname: Field
authors.forename: K
authors.initials: K
authors.lastname: Graupner
mesh_terms: D000838:Anions; D004136:Dinitrobenzenes / Q000737:chemistry*; D004583:Electrons; D008958:Models, Molecular; D013816:Thermodynamics
chemical_list: D000838:Anions; D004136:Dinitrobenzenes