Electronic state chromatography of lutetium cations

This is the authors' abstract. We don't add key points for this paper.

Relativistic effects have a profound impact on the electronic structure of the heaviest elements, and consequently on their chemical and physical properties. In order to investigate these effects, we developed an ion mobility spectrometer equipped with a cryogenic drift tube to measure the reduced mobilities of the ions of monoatomic lanthanides and actinides. As a benchmark, we conducted the first systematic study of lutetium cations ( Lu + ) drifting in helium at 298 K, resolving ground and metastable electronic states using electronic state chromatography. We compared the state-specific mobilities with predictions based on state-of-the-art calculations, and they show very good agreement. Our work paves the way for atomic structure studies in the region of the superheavy elements and provides a powerful experimental approach for exploring ion-neutral interactions and electronic configuration effects in heavy element systems.