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arXiv:2303.17528 · Physical Review A

Chemical reactions of ultracold alkaline-earth-metal diatomic molecules

Hela Ladjimi, Michał Tomza

Published Aug 24, 2023• 8 citations
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Abstract

The authors predict that alkaline-earth-metal diatomic molecules are chemically unstable at ultralow temperatures. The authors find that trimer formation reactions are highly energetic for all molecules, including homonuclear dimers, and atom-exchange reactions are energetically allowed for all heteronuclear combinations.
DOI
10.1103/physreva.108.l021302

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We investigate the energetics of reactions involving pairs of alkali-metal dimers. Atom exchange reactions to form homonuclear dimers are energetically allowed for some but not all of the heteronuclear dimers. We carry out high-level electronic structure calculations on the potential energy surfaces of all the heteronuclear alkali-metal trimers and show that trimer formation reactions are always energetically forbidden for low-lying singlet states of the dimers. The results have important implications for the stability of quantum gases of alkali-metal dimers.
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