| 2. |
- dos Santos, S. Fonseca, et al.
(författare)
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Dissociative recombination of N2H
- 2016
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Ingår i: Physical Review A. - 2469-9926. ; 94:2
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Tidskriftsartikel (refereegranskat)abstract
- The direct and indirect mechanisms of dissociative recombination of N2H+ are theoretically studied. At low energies, the electron capture is found to be driven by recombination into bound Rydberg states, while at collision energies above 0.1 eV, the direct capture and dissociation along electronic resonant states becomes important. Electron-scattering calculations using the complex Kohn variational method are performed to obtain the scattering matrix as well as energy positions and autoionization widths of resonant states. Potential-energy surfaces of electronic bound states of N2H and N2H+ are computed using structure calculations with the multireference configuration interaction method. The cross section for the indirect mechanism is calculated using a vibrational frame transformation of the elements of the scattering matrix at energies just above the ionization threshold. Here vibrational excitations of the ionic core from v = 0 to v = 1 and v = 2 for all three normal modes are considered and autoionization is neglected. The cross section for the direct dissociation along electronic resonant states is computed with wave-packet calculations using the multiconfiguration time-dependent Hartree method, where all three internal degrees of freedom are considered. The calculated cross sections are compared to measurements.
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| 3. |
- Orel, A. E., et al.
(författare)
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Resonances in dissociative recombination : Trends and patterns
- 2009
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Ingår i: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 192, s. 012006-
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Tidskriftsartikel (refereegranskat)abstract
- In dissociative recombination, the kinetic energy of the incident electron is transferred into excitation of the electrons of the target ion and then into kinetic energy of the fragments. In general, this proceeds via a resonance where the electron is temporarily trapped by the ion, leading to efficient energy transfer. The study of dissociative recombination is the study of these resonances, Rydberg states converging to the ground and excited states of the ion. For a number of systems, we have studied the electronic states involved in dissociative recombination, including the ground and excited states of the ion, the resonant states and the bound Rydberg states of the system, by combining electron scattering calculations with multi-reference configuration interaction quantum chemistry calculations. We will report on trends and patterns in these resonance states. We will discuss studies of dissociative recombination of the rare-gas ions, moving down the periodic table from He+ 2 to Ne+ 2 to Ar+ 2, where the ground electronic state of the ion is constant, but its polarizability increases. We will also present results on isoelectronic polyatomic systems, such as HCO + and HCNH+, as well as the effects of changing the electronic structure slightly such as HCN+/HNC+ and H 2CO+.
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