Hassium

Hassium was first created in 1984 at the GSI laboratory in Darmstadt by the team of Peter Armbruster and Gottfried Munzenberg, by fusing iron and lead nuclei. It was named after the German state of Hesse, in Latin Hassia, where the Darmstadt laboratory lies. Hassium is an intensely radioactive synthetic metal, existing only for fractions of a second, though its chemistry has been studied on a handful of atoms and found to match expectations for its group. Made by fusing iron and lead nuclei, hassium exists for at most seconds and usually a fraction of a second, so that every atom must be identified individually by the chain of radioactive decays it leaves behind.

A landmark experiment in 2001 succeeded in studying hassium's actual chemistry despite having only a handful of atoms to work with, confirming that hassium tetroxide behaves much like the corresponding osmium compound, volatile and chemically similar, direct evidence that the periodic table's predicted trends hold even for elements that exist for only fractions of a second and can never be gathered in bulk. Such single-atom chemistry experiments, requiring the coordinated effort of large international teams, remain among the most technically demanding in all of modern science.

Hassium's name honours the German Land of Hesse, the region surrounding Darmstadt where the GSI accelerator produced it and several of its neighbours, from Latin Hassia. It belongs to a small cluster of superheavy elements named for the places that made them, alongside darmstadtium for the city itself and dubnium for the rival Russian town, reflecting the handful of laboratories in the world capable of such work. Hassium has no ancient, mythological or alchemical tradition, being a synthetic element of the 1980s with no existence outside the laboratory; its modest distinction is that despite lasting only moments, enough atoms have been studied to confirm that it behaves chemically like a heavier cousin of osmium, as the periodic table predicts, a small triumph of chemistry at the very edge of what can be measured.

GSI itself, formally the Gesellschaft fur Schwerionenforschung, was founded in Darmstadt in 1969 specifically to build the heavy-ion accelerators capable of this kind of research, and the choice to locate it there, rather than any deeper historical connection to Hesse, is ultimately why so many elements ended up named for a modest German state and its capital city. The laboratory continues to operate today under the renamed GSI Helmholtz Centre for Heavy Ion Research, still producing new isotopes at the edge of the known chart of nuclides.