Transition metal, atomic number 106.
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.
Symbol Sg. Atomic mass 269.0 u. Group 6, period 7. Electron configuration [Rn] 5f14 6d4 7s2. Electrons per shell 2, 8, 18, 32, 32, 12, 2. State at room temperature: Solid. Melting point unknown, boiling point unknown. Discovered by Lawrence Berkeley National Laboratory.
Element data from Wikipedia, CC BY-SA 3.0.