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Anions formed by the perhalobenzene series C$$_6$$Cl$$_{n}$$F$$_{6-n}$$ ($n=0-6$) are studied computationally. All members of the series form both stable valence and stable non-valence anions. At the geometry of the neutral parents, only non-valence anions are bound, and the respective vertical electron affinities show values in the $20$ to $60$meV range. Valence anions show distorted non-planar structures, and one can distinguish two types of conformers. A-type conformers show puckered-ring structures and excess electrons delocalized over several C-Cl bonds [in case of C$$_6$$F$$_6^-$$, C-F bonds], while B-type conformers possess excess electrons essentially localized in a single C-Cl bond, which is accordingly strongly stretched and bent out-of-plane. For a specific anion, all conformers are close in energy (relative energies of less than $10$kJ/mol) and are connected by low-lying transition states. Accordingly, A-type and B-type conformers possess similar adiabatic electron affinities, however, their vertical detachment energies exhibit drastically different values, which should ease conformer distinction in photoelectron spectroscopy.
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A xenon collisional-radiative model applicable to electric propulsion devices: II. Kinetics of the 6 s , 6 p , and 5 d states of atoms and ions in Hall thrusters
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1361-6595/ab30b7
