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arXiv · 2303.17528

Chemical reactions of ultracold alkaline-earth-metal diatomic molecules

Abstract

We study the energetics of chemical reactions between ultracold ground-state alkaline-earth-metal diatomic molecules. We show that the atom-exchange reactions forming homonuclear dimers are energetically allowed for all heteronuclear alkaline-earth-metal combinations. We perform high-level electronic structure calculations on the potential energy surfaces of all possible homo- and heteronuclear alkaline-earth-metal trimers and show that trimer formation is also energetically possible in collisions of all considered dimers. Interactions between alkaline-earth-metal diatomic molecules lead to the formation of deeply bound reaction complexes stabilized by large non-additive interactions. We check that there are no barriers to the studied chemical reactions. This means that all alkaline-earth-metal diatomic molecules are chemically unstable at ultralow temperature, and optical lattice or shielding schemes may be necessary to segregate the molecules and suppress losses.

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BibTeXRIS

Hela Ladjimi, Michał Tomza. 2023-11-30. Chemical reactions of ultracold alkaline-earth-metal diatomic molecules. https://doi.org/10.1103/physreva.108.l021302

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