| Atomic Number: |
106 |
| Atomic Symbol: |
Sg |
| Atomic Weight: |
263 |
| Electron Configuration: |
[Rn]7s25f146d4 |
In June
1974, members of the Joint Institute for Nuclear Research
in Dubna, U.S.S.R., reported their discovery of Element
106, which they reported to have synthesized. Glenn Seaborg
was part of this group, and the element was named in his
honor. Seaborgium is often still referred to as Element
106 because the international committee in charge of names
changed the rules. They decided retroactively it couldn't
be named after a living person.
In
September 1974, workers of the Lawrence Berkeley and Livermore
Laboratories also claimed creation Element 106 "without
any scientific doubt." The LBL and LLL Group used
the Super HILAC to accelerate 18O ions onto a 249Cf target.
Element
106 was created by the reaction 249Cf(18O, 4N)263X, which
decayed by alpha emission to rutherfordium, and then by
alpha emission to nobelium, which in turn further decayed
by alpha between daughter and granddaughter. The element
so identified had alpha energies of 9.06 and 9.25 MeV
with a half-life of 0.9 +/- 0.2 s.
At
Dubna, 280-MeV ions of 54Cr from the 310-cm cyclotron
were used to strike targets of 206Pb, 207Pb, and 208Pb,
in separate runs. Foils exposed to a rotating target disc
were used to detect spontaneous fission activities. The
foils were etched and examined microscopically to detect
the number of fission tracks and the half-life of the
fission activity.
Other
experiments were made to aid in confirmation of the discovery.
Neither the Dubna team nor the Berkeley-Livermore Group
has proposed a name as of yet for element 106 (unnilhexium).