https://doi.org/10.1140/epjd/s10053-021-00112-9
Regular Article - Clusters and Nanostructures
Submersion of rubidium clusters in helium nanodroplets
1
Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25, 6020, Innsbruck, Austria
2
Faculté des Sciences IV, Université Libanaise, Haouch El-Omara, Zahlé, Lebanon
Received:
3
November
2020
Accepted:
9
December
2020
Published online:
12
April
2021
Alkali atoms and small clusters are known to reside on the surface of a helium droplet rather than its inside as most other dopant species. A theoretical investigation suggested that alkali clusters (Li–Rb) exceeding a certain critical size can become submerged in the droplet, which was experimentally confirmed for sodium and potassium. Here, we report an analogous experimental study of rubidium cluster submersion by means of electron impact mass spectrometry. We recorded size distributions of Rb cluster ions at various electron energies between 8 and 160 eV. Our data suggest that Rb clusters attached to helium droplets undergo a gradual submersion transition similar to potassium, ultimately leading to the full submersion of clusters larger than 
atoms. Our findings are consistent with previous theoretical and experimental studies.
Supplementary Information The online version supplementary material available at https://doi.org/10.1140/epjd/s10053-021-00112-9.
© The Author(s) 2021
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