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106 Sg

Seaborgium

transition metal

Properties

Property Value
Atomic Mass269 amu
Categorytransition metal
Group6
Period7
Electron Configuration[Rn] 5f14 6d4 7s2
Oxidation States6, 5, 4, 3, 0
Discovered ByAlbert Ghiorso, Lawrence Berkeley National Laboratory (1974)

About Seaborgium

Seaborgium sits below tungsten and molybdenum in group 6, and it is one of the heaviest elements anyone has done real chemistry with. The Berkeley team made it in 1974 by hammering ²⁴⁹Cf with ¹⁸O ions, identifying it through its α-decay chain back to known nuclides. The longer-lived isotope Sg-269 lasts about 14 minutes, which is just enough headroom to chase down its chemistry one atom at a time. The classic experiments — done by groups at GSI Darmstadt and PSI — produce SgO₂Cl₂ in a flowing oxygen-chlorine stream and watch how it adsorbs on a temperature-gradient column. The retention temperature lines up with WO₂Cl₂ and MoO₂Cl₂, confirming that even at Z = 106 the periodic table still works: seaborgium is genuinely a heavier tungsten. Naming it became a flashpoint because IUPAC's then-rule against living-person eponyms collided with Glenn Seaborg, the chemist who co-discovered ten transuranic elements and was very much alive. The community pushed back, the rule bent, and 'seaborgium' was made official in 1997.

Fun Fact

Glenn Seaborg is the only person in history to have a chemical element named after him while still alive — he was reportedly delighted by the honor, joking that he could now spell his name using only element symbols: Sg.

Common Uses

  • Single-atom oxychloride chemistry validating group 6 periodic trends
  • Probing relativistic effects on 6d⁴ 7s² electron configuration
  • Cross-section measurements for ²⁴⁹Cf(¹⁸O,xn) hot-fusion reactions
  • Calibrating α-decay chain identification of superheavy nuclei
  • Reference for predicting bohrium and hassium chemistry
  • No commercial applications — only ever produced atom-by-atom

Frequently Asked Questions

What is the atomic mass of Seaborgium?
The atomic mass of Seaborgium (Sg) is 269 amu.
What is the electron configuration of Seaborgium?
The electron configuration of Seaborgium is [Rn] 5f14 6d4 7s2.
What group is Seaborgium in?
Seaborgium is in Group 6, Period 7 of the periodic table.