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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
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
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
Sources: CRC Handbook of Chemistry
and Physics and the American Chemical Society.