ELEMENTLE

Element 106 · Transition Metal

Seaborgium

Period 7 · Group 6

Seaborgium is a synthetic element with symbol Sg and atomic number 106. Its most stable isotope 271Sg has a half-life of 1.9 minutes. A more recently discovered isotope 269Sg has a potentially slightly longer half-life (ca.

Three reasons Seaborgium stands out

  1. 1

    Named after a Nobel laureate in chemistry.

  2. 2

    The scientist it was named after was still alive when the naming occurred, making it exceptionally rare to be honoured this way.

  3. 3

    It was first synthesised in 1974 and only a handful of atoms have ever been produced.

A living scientist enters the periodic table

Seaborgium was named for Glenn Seaborg while he was still alive, an unusual honor that stirred debate. Experiments involving only a handful of atoms found volatile compounds resembling those of tungsten and molybdenum. Such results test whether periodic trends survive enormous nuclear charge.

Seaborgium at a glance
Atomic number / protons106
SymbolSg
Family (Elementle)Transition Metal
Classification (PubChem)Transition metal
Period7
Group6
Atomic mass (u)269.128
Standard stateBulk state not experimentally established
Electron configuration[Rn]7s2 5f14 6d4
Reported oxidation states6, 5, 4, 3, 0
Electronegativity (Pauling)Not available
Atomic radius (pm)Not available
First ionization energy (eV)Not available
Electron affinity (eV)Not available
Density (g/cm³)Not available
Melting pointNot available
Boiling pointNot available
Discovery (PubChem)1974

Values are reference data, not a specification for every temperature, pressure, or allotrope. Unknown properties are left unavailable. Superheavy-element predictions remain uncertain.

Sources & further reading

PubChem: Seaborgium · Seaborgium on Wikipedia

The introduction and original editorial story are adapted from Wikipedia contributors via Periodic-Table-JSON. Element descriptions and their adaptations are available under CC BY-SA 3.0. Numerical attributes use the PubChem periodic-table dataset, retrieved September 22, 2026.