Seaborgium

TRANSITION METAL · GROUP 6 · PERIOD 7
106
Sg
Seaborgium
269

Atomic Data

Atomic Number106
SymbolSg
Atomic Weight269 u
Density (STP)N/A
Melting PointN/A °C (None K)
Boiling PointN/A °C (None K)
Electronegativity:
Electron Config.1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 5f14 6s2 6p6 6d4 7s2
Oxidation States+6
Phase at STPSolid
CategoryTransition Metal
Period / Group7 / 6
CAS Number54038-81-2

Electron Configuration

[Rn] 5f14 6d4 7s2

Shell n Subshell Electrons Cumulative
K11s22
L22s24
L22p610
M33s212
M33p618
M33d1028
N44s230
N44p636
N44d1046
N44f1460
O55s262
O55p668
O55d1078
O55f1492
P66s294
P66p6100
P66d4104
Q77s2106
Total 106 106

Isotopes of Seaborgium

Seaborgium has two naturally occurring stable isotopes. The most abundant is ²⁶⁹Sg, comprising None% of all naturally occurring Seaborgium.

Isotope Symbol Protons Neutrons Abundance Stability
Seaborgium-269²⁶⁹Sg106163traceStable
Seaborgium-271²⁷¹Sg106165traceStable

Abundance & Occurrence

Seaborgium is present in Earth's crust at approximately trace amounts by mass and at approximately trace amounts by mass throughout the universe.

Earth's Crust (ppm by mass)

Seaborgium
None ppm
Silicon (ref.)
277,000 ppm
Oxygen (ref.)
461,000 ppm

Universe (ppm by mass)

Seaborgium
None ppm
Helium (ref.)
230,000 ppm
Hydrogen (ref.)
739,000 ppm

Discovery & History

1974
Albert Ghiorso et al. (Lawrence Berkeley): Ghiorso's team synthesised element 106 by bombarding californium-249 with oxygen-18 ions in the Super-HILAC, producing four atoms; they proposed the name seaborgium in honour of Glenn T. Seaborg: controversially, while Seaborg was still alive.
1974
Flerov's team (Dubna): Dubna simultaneously reported synthesis by bombarding lead-208 with chromium-54 ions; both claims were eventually validated and Dubna received partial credit, but Berkeley's synthesis was confirmed more rigorously.
1997
IUPAC: IUPAC formally named element 106 seaborgium: the first element named after a living person at the time of naming; Seaborg himself called it the greatest honour of his career.

Safety & Handling

  • Alpha radiation: Seaborgium isotopes are alpha emitters; Sg-271 (t½ = 1.9 min) is among the longer-lived, meaning chemical experiments must be performed extremely rapidly after synthesis.
  • No bulk hazard: Seaborgium has only been produced a few atoms at a time; there is no practical bulk radiological or chemical hazard.
  • Short half-life operations: Chemistry experiments on single seaborgium atoms must be fully automated and performed within seconds of synthesis; personnel are remote from the detection equipment during operation.
  • Regulatory controls: All work is conducted at licensed accelerator facilities under comprehensive radiation protection programmes.

Real-World Uses

  • Superheavy element chemistry: Seaborgium (Sg) chemistry experiments demonstrate that Sg behaves like the lighter Group 6 elements tungsten and molybdenum in forming volatile oxide tetrachlorides and oxychlorides, confirming the general validity of the periodic law at Z=106.
  • Nuclear physics: Seaborgium isotope production and decay measurement contribute to the systematic mapping of nuclear properties (alpha and spontaneous fission decay) in the transition region between lighter actinides and the predicted superheavy island of stability.
  • No commercial applications: Seaborgium is produced a few atoms at a time with half-lives of seconds to minutes; no practical applications are possible or envisaged.

Downloadable Resources

Free periodic table reference sheets for classrooms, study sessions, and laboratory use.

Frequently Asked Questions

Has seaborgium ever been used for anything?

No. Seaborgium has no practical applications. Its most stable isotope (Sg-271) has a half-life of about 2.4 minutes. It is produced a few atoms at a time solely for fundamental nuclear and chemical research. Seaborgium chemistry has been studied in experiments involving individual atoms of the element, confirming it behaves as a group 6 element (like chromium, molybdenum, and tungsten).

How many atoms of seaborgium have been made?

Seaborgium is produced in particle accelerators at rates of perhaps a few atoms per day under optimal conditions. Individual atoms are studied the moment they are produced, before they decay. Seaborgium chemistry experiments have been performed with just a handful of atoms at a time, using rapid online chemical separation techniques.

Is seaborgium radioactive?

Yes, all isotopes of seaborgium are radioactive. The most stable known, Sg-271, has a half-life of about 2.4 minutes. Most others decay in seconds. All seaborgium atoms are produced one at a time in particle accelerators and decay almost immediately.

How did seaborgium get its name?

Seaborgium was named after Glenn T. Seaborg, the American chemist who co-discovered plutonium and nine other transuranium elements and received the 1951 Nobel Prize in Chemistry. Controversially, seaborgium was named after Seaborg while he was still alive (he died in 1999): at the time this was unprecedented for an element name. IUPAC initially objected but eventually approved the name seaborgium in 1997.