Naming of element 106 disputed by international committee

October 14, 1994

By Lynn Yarris,

In a surprising and immediately controversial move, a committee for the British-based International Union of Pure and Applied Chemistry (IUPAC) has recommended against the name "seaborgium" for element 106. The name had been chosen by the team that discovered 106 to honor Glenn T. Seaborg, Nobel Prize winning chemist and associate director-at-large of LBL (see Currents, March 18, 1994).

The IUPAC committee's decision, which was announced in this week's issue of Chemical and Engineering News (C&EN), was actually made at a meeting in Hungary on August 31 for the purpose of naming elements 101 through 109. Prior to voting on nomenclature, the committee adopted, by a vote of 16-4, a new rule that no element should be named for a living person. (The vote to replace the name seaborgium passed 18-2.) Both Albert Einstein and Enrico Fermi were alive when elements 99 and 100 were named for them.

In response to the announcement, LBL Director Charles Shank issued a statement expressing "dismay" with the IUPAC committee's rejection of the name seaborgium.

"Credit for the discovery of element 106 is undisputed and the discovery team unanimously selected the name seaborgium," Shank said. "There has never been any debate about the right of acknowledged discoverers to name an element. We will strongly defend this privilege."

Element 106 was first created and identified in 1974 at LBL by a team of researchers led by LBL physicist Albert Ghiorso and LLNL chemist Kenneth Hulet. It was confirmed in 1993 in an experiment at the 88-Inch Cyclotron led by Ken Gregorich and Darleane Hoffman of the Nuclear Science Division. The name seaborgium, with the chemical symbol "Sg," was announced last March at the national meeting of the American Chemical Society. The ACS's own nomenclature committee promptly adopted the name.

DuPont chemist Anthony Arduengo III, who was one of five Americans on the 20-member IUPAC nomenclature committee (the other members were from Australia, Finland, Hungary, Japan, the Netherlands, Russia, South Africa, Spain, Sweden, Switzerland, and the United Kingdom), defended the committee's decision to ignore the wishes of 106's discoverers.

"Discoverers don't have a right to name an element," he told C&EN. "They have a right to suggest a name. And, of course, we didn't infringe on that at all."

However, as Seaborg noted in the C&EN article, "This would be the first time in history that the acknowledged and uncontested discoverers of an element are denied the privilege of naming it."

The IUPAC nomenclature committee's decisions came on the heels of the rulings of another international committee that spent six years resolving disputed claims of discovery. The first committee, called the Transfermium Working Group (TWG), was jointly convened in 1986 by IUPAC and the International Union of Pure and Applied Physics. It reviewed research data submitted from LBL, the Joint Institute for Nuclear Research in Dubna, Russia, and GSI in Darmstadt, Germany.

The TWG gave full credit for the discovery of 106 to the Ghiorso-Hulet team. Although the TWG ruled that LBL and the Russian group should share credit for the discovery of elements 104 and 105 (a decision with which Seaborg and Ghiorso disagreed), IUPAC's nomenclature committee elected to recommend the two Russian-proposed names of "dubnium" and "joliotium." The committee then assigned the name "rutherfordium," which had been proposed by the LBL group for 104, to element 106. The name "bohrium" was recommended for 107 (instead of GSI's choice of nielsbohrium), and "hahnium" for 108 (instead of GSI's choice of hassium). Hahnium had originally been proposed by the LBL group for element 105. The German proposal of "meitnerium" for 109 was allowed to stand, as were the names proposed for elements 101, 102, and 103 --"mendelevium," "nobelium," and "lawrencium," respectively.

These name recommendations must be ratified by the full IUPAC council, which meets in England next August. The U.S. National Committee for IUPAC is planning to issue a letter requesting that until then, in accordance with IUPAC rules, the recommended names be clearly labeled as "provisional." ACS Board of Directors Chair Paul Walter has also expressed disappointment with the IUPAC committee's decision.