Transfermium Wars

The names for the chemical elements 104 to 106 were the subject of a major controversy starting in the 1960s, described by some nuclear chemists as the Transfermium Wars[1][2] because it concerned the elements following fermium (element 100) on the periodic table.

This controversy arose from disputes between American scientists and Soviet scientists as to which had first isolated these elements. The final resolution of this controversy in 1997 also decided the names of elements 107 to 109.

Controversy

By convention, naming rights for newly discovered chemical elements go to their discoverers. For elements 104, 105, and 106, there was a controversy between Soviet researchers at the Joint Institute for Nuclear Research and American researchers at Lawrence Berkeley National Laboratory regarding which group had discovered them first. Both parties suggested their own names for elements 104 and 105, not recognizing the other's name.

The American name of seaborgium for element 106 was also objectionable to some, because it referred to American chemist Glenn T. Seaborg who was still alive at the time this name was proposed.[3] (Einsteinium and fermium had also been proposed as names of new elements while Einstein and Fermi were still living, but only made public after their deaths, due to Cold War secrecy.)

Opponents

The two principal groups which were involved in the conflict over element naming were:

and, as a kind of arbiter,

  • The IUPAC Commission on Nomenclature of Inorganic Chemistry, which introduced its own proposal to the IUPAC General Assembly.

The German group at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, who had (undisputedly) discovered elements 107 to 109, were dragged into the controversy when the Commission suggested that the name "hahnium", proposed for element 105 by the Americans, be used for GSI's element 108 instead.

Preferred names
Group Atomic number Name Eponym
American 104 rutherfordium Ernest Rutherford
105 hahnium Otto Hahn
106 seaborgium Glenn T. Seaborg
Russian 104 kurchatovium Igor Kurchatov
105 nielsbohrium Niels Bohr

Darmstadt

The names suggested for the elements 107 to 109 by the German group were:[4]

Atomic number Name Eponym
107 nielsbohrium Niels Bohr
108 hassium Hesse, Germany
109 meitnerium Lise Meitner

IUPAC

In 1994, the IUPAC Commission on Nomenclature of Inorganic Chemistry proposed the following names:

Atomic number Name Eponym
104 dubnium Dubna, Russia
105 joliotium Frédéric Joliot-Curie
106 rutherfordium Ernest Rutherford
107 bohrium Niels Bohr
108 hahnium Otto Hahn
109 meitnerium Lise Meitner

This attempted to resolve the dispute by sharing the namings of the disputed elements between Russians and Americans, replacing the name for 104 with one honoring the Dubna research center, and not naming 106 after Seaborg.

Objections to the IUPAC 94 proposal

This solution drew objections from the American Chemical Society (ACS) on the grounds that the right of the American group to propose the name for element 106 was not in question, and that group should have the right to name the element. Indeed, IUPAC decided that the credit for the discovery of element 106 should be awarded to Berkeley.

Along the same lines, the German group protested against naming element 108 by the American suggestion "hahnium", mentioning the long-standing convention that an element is named by its discoverers.[5]

In addition, given that many American books had already used rutherfordium and hahnium for 104 and 105, the ACS objected to those names being used for other elements.

In 1995, IUPAC abandoned the controversial rule and established a committee of national representatives aimed at finding a compromise. They suggested seaborgium for element 106 in exchange for the removal of all the other American proposals, except for the established name lawrencium for element 103. The equally entrenched name nobelium for element 102 was replaced by flerovium after Georgy Flerov, following the recognition by the 1993 report that that element had been first synthesized in Dubna. This was rejected by American scientists and the decision was retracted.[6] The name flerovium was later used for element 114.[7]

Resolution (IUPAC 97)

In 1996, IUPAC held another meeting, reconsidered all names in hand, and accepted another set of recommendations; finally, it was approved and published in 1997 on the 39th IUPAC General Assembly in Geneva, Switzerland.[8] Element 105 was named dubnium (Db), after Dubna in Russia, the location of the JINR; the American suggestions were used for elements 102, 103, 104, and 106. The name dubnium had been used for element 104 in the previous IUPAC recommendation. The American scientists "reluctantly" approved this decision.[9] IUPAC pointed out that the Berkeley laboratory had already been recognized several times, in the naming of berkelium, californium, and americium, and that the acceptance of the names rutherfordium and seaborgium for elements 104 and 106 should be offset by recognizing JINR's contributions to the discovery of elements 104, 105, and 106.[10]

The following names were agreed in 1997 on the 39th IUPAC General Assembly in Geneva, Switzerland:

Atomic number Name Eponym
104 rutherfordium Ernest Rutherford
105 dubnium Dubna, Russia
106 seaborgium Glenn Theodore Seaborg
107 bohrium Niels Bohr
108 hassium Hesse, Germany
109 meitnerium Lise Meitner

Thus, the convention of the discoverer's right to name their elements was respected for elements 106 to 109,[11] and the two disputed claims were "shared" between the two opponents.

Summary

Summary of element naming proposals and final decisions for elements 101–112 (those covered in the TWG report):[9]

Atomic numberSystematicAmericanRussianGermanCompromise 92IUPAC 94ACS 94IUPAC 95IUPAC 97Present
101unniluniummendelevium——mendeleviummendeleviummendeleviummendeleviummendeleviummendelevium
102unnilbiumnobeliumjoliotium—joliotiumnobeliumnobeliumfleroviumnobeliumnobelium
103unniltriumlawrenciumrutherfordium—lawrenciumlawrenciumlawrenciumlawrenciumlawrenciumlawrencium
104unnilquadiumrutherfordiumkurchatovium—meitneriumdubniumrutherfordiumdubniumrutherfordiumrutherfordium
105unnilpentiumhahniumnielsbohrium—kurchatoviumjoliotiumhahniumjoliotiumdubniumdubnium
106unnilhexiumseaborgium——rutherfordiumrutherfordiumseaborgiumseaborgiumseaborgiumseaborgium
107unnilseptium——nielsbohriumnielsbohriumbohriumnielsbohriumnielsbohriumbohriumbohrium
108unniloctium——hassiumhassiumhahniumhassiumhahniumhassiumhassium
109unnilennium——meitneriumhahniummeitneriummeitneriummeitneriummeitneriummeitnerium
110ununniliumhahniumbecquereliumdarmstadtium—————darmstadtium
111unununium——roentgenium—————roentgenium
112ununbium——copernicium—————copernicium

See also

References
  1. "The Transfermium Wars". Bulletin of the Atomic Scientists. Educational Foundation for Nuclear Science, Inc. 51 (1): 5. 1995. ISSN 0096-3402.
  2. Fox, Stuart (2009-06-29). "What's It Like to Name An Element on the Periodic Table?". Popular Science.
  3. Seaborg commented wryly at a talk in 1995 that "There has been some reluctance on the part of the Commission for Nomenclature of Inorganic Chemistry of the International Union of Pure and Applied Chemistry to accept the name because I'm still alive and they can prove it, they say." (An Early History of LBNL by Dr. Glenn T. Seaborg "Archived copy". Archived from the original on 2004-10-21. Retrieved 2007-03-28.CS1 maint: archived copy as title (link))
  4. IUPAC verabschiedet Namen für schwere Elemente
  5. http://www.gsi.de/documents/DOC-2003-Jun-35-5.pdf (in German).
  6. Hoffman, D. C.; Ghiorso, A.; Seaborg, G. T. (2000). The Transuranium People: The Inside Story. World Scientific. pp. 389–394. ISBN 978-1-78326-244-1.
  7. Loss, R. D.; Corish, J. (2012). "Names and symbols of the elements with atomic numbers 114 and 116 (IUPAC Recommendations 2012)" (PDF). Pure and Applied Chemistry. 84 (7): 1669–72. doi:10.1351/PAC-REC-11-12-03. S2CID 96830750. Retrieved 21 April 2018.
  8. Bera, J. K. (1999). "Names of the Heavier Elements". Resonance. 4 (3): 53–61. doi:10.1007/BF02838724. S2CID 121862853.
  9. Hoffman, D. C.; Ghiorso, A.; Seaborg, G. T. (2000). The Transuranium People: The Inside Story. Imperial College Press. pp. 369–399. ISBN 978-1-86094-087-3.
  10. "Names and symbols of transfermium elements (IUPAC Recommendations 1997)". Pure and Applied Chemistry. 69 (12): 2471–2474. 1997. doi:10.1351/pac199769122471.
  11. Except for the change from nielsbohrium to bohrium, following the convention that elements are named after last names of scientists only.
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