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arXiv:2203.12974 · The Journal of Chemical Physics

Spin-state-controlled chemi-ionization reactions between metastable helium atoms and ground-state lithium atoms

Tobias Sixt, Frank Stienkemeier, Katrin Dulitz

Published Mar 21, 2022• 1 citation
arXivHTMLPDF

Abstract

We demonstrate the control of 4He(23S1)–7Li(22S1/2) chemi-ionization reactions by all-optical electron-spin-state preparation of both atomic species prior to the collision process. Our results demonstrate that chemi-ionization is strongly suppressed (enhanced) for non-spin-conserving (spin-conserving) collisions at thermal energies. These findings are in good agreement with a model based on spin angular momentum coupling of the prepared atomic states to the quasi-molecular states. Small deviations from the model indicate the contribution of the 4Σ+ channel to the reaction rate, which is in violation of spin conservation.

DOI
10.1063/5.0083842

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