- Hassium (Hs) is a synthetic, radioactive element with atomic number 108, positioned in Group 8 of the periodic table, directly beneath osmium.
- It is a transactinide and belongs to the 6d transition metals. Its predicted electron configuration is [Rn] 5f¹⁴ 6d⁶ 7s², aligning with Group 8 chemistry, although relativistic effects influence its orbital energies.
- Hassium is expected to show a predominant oxidation state of +8, similar to osmium and ruthenium, along with lower states such as +6 and +4. The atomic structure contains one hundred and eight protons, with roughly one hundred and sixty-nine to one hundred and seventy-three neutrons depending on the isotope, and one hundred and eight electrons distributed in seven shells.
- The most stable known isotope, hassium-270 (²⁷⁰Hs), has a half-life of about 10 seconds, while most others decay within milliseconds.
- Hassium was first synthesized in 1984 at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany, by a team led by Peter Armbruster and Gottfried Münzenberg. The team bombarded lead-208 (²⁰⁸Pb) targets with iron-58 (⁵⁸Fe) ions in a heavy-ion accelerator, producing hassium-265 (²⁶⁵Hs). This experiment confirmed the existence of element 108, and further studies produced additional isotopes, solidifying its discovery.
- The name hassium comes from Hassia, the Latin name for the German state of Hesse, where the discovery took place. The element’s symbol, Hs, was officially adopted in 1997 after IUPAC resolved a series of naming disputes involving superheavy elements.
- Hassium has no practical applications due to its instability and production in only atom-scale amounts. It is studied solely for research purposes, advancing the understanding of transactinide elements and testing predictions about relativistic effects in heavy nuclei.
- Chemically, hassium is predicted to behave much like osmium. Experiments conducted with a few atoms have shown that hassium forms a volatile tetroxide, hassium(VIII) oxide (HsO₄), paralleling osmium tetroxide (OsO₄). This confirmed its Group 8 character, making hassium the first superheavy element whose oxide chemistry was experimentally studied.
- Biologically, hassium has no natural function and is considered radiotoxic. Its extreme scarcity and rapid decay mean it poses no biological risk outside research laboratories.
- Environmentally, hassium is not found in nature. It is produced only in advanced nuclear research facilities, exists for mere seconds, and leaves no lasting environmental footprint.
