Extent of the Periodic Table, Relativistic Atomic Effects, and the Island of Stability

Determine how far the periodic table predicted by quantum mechanics may extend, characterize how relativistic effects influence atomic structure, and locate the island of enhanced nuclear stability around proton number Z approximately 114 and neutron number N approximately 184.

Background

The paper motivates photon-based mass spectrometry and laser spectroscopy of heavy and superheavy elements, including thorium and thorium-containing molecular ions. These techniques provide complementary information about nuclear binding energies, nuclear moments, and atomic structure. In that broader research context, the authors identify three unresolved questions: the maximum extent of the quantum-mechanical periodic table, the role of relativistic effects in atomic structure, and the location of the predicted island of enhanced nuclear stability near Z approximately 114 and N approximately 184. The questions are presented as open issues highlighted in recent review literature, rather than as problems resolved by the experimental work reported in the paper.

References

High-precision mass spectrometry and laser spectroscopy provide complementary information on nuclear binding energies, nuclear moments, and atomic structure , important for addressing open questions highlighted in recent reviews (see, e.g., ): how far the periodic table predicted by quantum mechanics may extend, how relativistic effects influence atomic structure, and the location of the so-called island of enhanced stability around $Z\sim114$ and $N\sim184$.

— Cyclotron-Frequency Stability via Single-Ion Fluorescence in a Penning Trap with a Cryogen-Free Superconducting Magnet  (2609.16713 - Schupeta et al., 15 Sep 2026) in Section 1, Introduction