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arXiv · 2405.06514

Autodetachment of diatomic carbon anions from long-lived high-rotation quartet states

Viviane C. Schmidt·Roman Čurík·Milan Ončák·Klaus Blaum·Sebastian George·Jürgen Göck·Manfred Grieser·Florian Grussie·Robert von Hahn·Claude Krantz·Holger Kreckel·Oldřich Novotný·Kaija Spruck·Andreas Wolf
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Abstract

Highly excited C$_2{}^{-}$ ions prominently feature electron detachment at a mean decay time near 3 milliseconds with hitherto unexplained origin. Considering various sources of unimolecular decay, we attribute the signal to the electronic C$^4\Sigma^+_u$ state. Quartet C$_2{}^{-}$ levels are found to be stabilized against autodetachment by high rotation. Time constants of their rotationally assisted autodetachment into levels opening energetically at lower rotation are calculated by a theory based on the non-local resonance model. For some final levels of significantly less rotation the results conclusively explain the puzzling observations.

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Viviane C. Schmidt, Roman Čurík, Milan Ončák, Klaus Blaum, Sebastian George, Jürgen Göck, Manfred Grieser, Florian Grussie, Robert von Hahn, Claude Krantz, Holger Kreckel, Oldřich Novotný, Kaija Spruck, Andreas Wolf. 2024-05-10. Autodetachment of diatomic carbon anions from long-lived high-rotation quartet states. https://doi.org/10.1103/physrevlett.133.183001

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