# Ab Initio Study of Chemical Reactions of Cold SrF and CaF Molecules with Alkali-Metal and Alkaline-Earth-Metal Atoms

## TL;DR

This study uses ab initio calculations to explore the energetics and potential energy surfaces of SrF and CaF molecules reacting with alkali-metal atoms, revealing barrierless reactions with lithium and prospects for cooling applications.

## Contribution

It provides detailed potential energy surfaces and demonstrates that certain reactions are barrierless, advancing understanding of cold molecule-atom interactions.

## Key findings

- SrF+Li and SrF+Sr reactions are barrierless
- Potential energy surfaces are deep with strong anisotropy
- Collisions likely have a strong inelastic character

## Abstract

We investigate the energetics of the atom exchange reaction in the SrF+alkali-metal atom and CaF+alkali-metal atom systems. Such reactions are possible only for collisions of SrF and CaF with the lithium atoms, while they are energetically forbidden for other alkali-metal atoms. Specifically, we focus on SrF interacting with Li, Rb, and Sr atoms and use ab initio methods to demonstrate that the SrF+Li and SrF+Sr reactions are barrierless. We present potential energy surfaces for the interaction of the SrF molecule with the Li, Rb, and Sr atoms in their energetically lowest-lying electronic spin states. The obtained potential energy surfaces are deep and exhibit profound interaction anisotropies. We predict that the collisions of SrF molecules in the rotational or Zeeman excited states most likely have a strong inelastic character. We discuss the prospects for the sympathetic cooling of SrF and CaF molecules using ultracold alkali-metal atoms.