|
Known properties |
Name, Symbol, Number | Seaborgium, Sb, 106 |
Chemical series | Transition metals |
Group, Period, Block | 15, 5 , d |
Appearance | unknown; probably metallic, silvery white or gray |
Atomic weight | [266] amu |
Electron configuration | probably [Rn]5f14 6d4 7s2 |
e- 's per energy level | 2, 8, 18, 32, 32, 12, 2 |
State of matter | Presumably a solid |
Seaborgium is a
chemical element in the
periodic table that has the symbol Sg and
atomic number 106.
It was also known as "unnilhexium" (Unh), and at one time "rutherfordium" was suggested. Seaborgium is a
synthetic element whose most stable
isotope 266Sg has a
half-life of
30 seconds.
Element 106 was discovered almost simultaneously by two different laboratories.
In June
1974, a
Soviet team led by G. N. Flerov at the
Joint Institute for Nuclear Research[?] at
Dubna[?] reported producing an isotope with mass number 259 and a half-life of 7ms, and in September
1974, an
American research team led by A. Ghiorso at the Lawrence Radiation Laboratory at the
University of California, Berkeley reported creating an isotope with mass number 263 and a half-life of 0.9s.
Because their work was independently confirmed first, the Americans suggested the name seaborgium to honor the American chemist
Glenn T. Seaborg.
This name was extremely controversial because Seaborg was alive.
An international committee decided in
1992 that the Berkeley and Dubna laboratories should share credit for the discovery.
An element naming controversy erupted and as a result IUPAC adopted Unnilhexium (symbol Unh) as a temporary name for this element.
In 1994 a committee of IUPAC recommended that element 106 be named rutherfordium and adopted a rule that no element can be named after a living person.
This ruling was fiercely objected to by the American Chemical Society[?].
In 1997, as part of a compromise involving elements 104 to 108 the name seaborgium for element 106 was recognized internationally.