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arXiv · 0705.1090

The structure and energetics of $^3$He and $^4$He nanodroplets doped with alkaline earth atoms

A. Hernando·R. Mayol·M. Pi·M. Barranco·F. Ancilotto·O. Bünermann·F. Stienkemeier
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Abstract

We present systematic results, based on density functional calculations, for the structure and energetics of $^3$He and $^4$He nanodroplets doped with alkaline earth atoms. We predict that alkaline earth atoms from Mg to Ba go to the center of $^3$He drops, whereas Ca, Sr, and Ba reside in a deep dimple at the surface of $^4$He drops, and Mg is at their center. For Ca and Sr, the structure of the dimples is shown to be very sensitive to the He-alkaline earth pair potentials used in the calculations. The $5s5p\leftarrow5s^2$ transition of strontium atoms attached to helium nanodroplets of either isotope has been probed in absorption experiments. The spectra show that strontium is solvated inside $^3$He nanodroplets, supporting the calculations. In the light of our findings, we emphasize the relevance of the heavier alkaline earth atoms for analyzing mixed $^3$He-$^4$He nanodroplets, and in particular, we suggest their use to experimentally probe the $^3$He-$^4$He interface.

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A. Hernando, R. Mayol, M. Pi, M. Barranco, F. Ancilotto, O. Bünermann, F. Stienkemeier. 2007-05-08. The structure and energetics of $^3$He and $^4$He nanodroplets doped with alkaline earth atoms. https://doi.org/10.1021/jp0701385

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