Hg231

Hg-231 is a hypothetical isotope of the element mercury (atomic number 80) with mass number 231. It is not among the isotopes of mercury that have been experimentally observed, and if it exists it would lie far from the line of stability on the neutron-rich side of the chart of nuclides. Nuclear models predict that Hg-231 would be highly unstable and decay rapidly.

Predicted decay modes for Hg-231 include beta-minus decay to Tl-231 and, with competing pathways, alpha decay to Pt-227. The exact decay scheme is uncertain and sensitive to details of nuclear structure such as shell effects and deformation. Accordingly, the estimated half-life would be very short, typically well below one second, often in the millisecond range or shorter, depending on the model.

Production of Hg-231 would require high-energy heavy-ion reactions, such as fusion-evaporation processes or projectile fragmentation/spallation in which neutron-rich mercury-like systems are formed transiently. Given its expected brief existence, experimental observation would be challenging and would rely on rapid separation techniques and decay-chain identification to confirm its presence.

Chemically, Hg-231 would behave as mercury insofar as its electron configuration governs chemistry; however, its fleeting lifetime would preclude practical chemical studies. The investigation of Hg-231 primarily informs nuclear structure and nucleosynthesis theory, contributing to understanding the limits of stability for heavy, neutron-rich nuclei and the processes that produce heavy elements in astrophysical environments.