Hassium is a synthetic chemical element named after the German state of Hesse.
Core Principles & Analysis
Hassium was first made in 1984 at GSI Darmstadt by fusing iron-58 with lead-208; its name comes from Hassia, the Latin name of Hesse, the German state where Darmstadt lies.
In 2002 chemists converted individual hassium-269 atoms, which live only around ten seconds, into volatile hassium tetroxide, HsO4, mirroring osmium's famous OsO4.
Isotopes near hassium-270 gain measurable stability from a predicted deformed nuclear shell closure at 162 neutrons, supporting the shell models behind the 'island of stability'.