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 due to 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.
Contents |
By convention, naming rights for newly discovered chemical elements go to their discoverers. However, for the elements 104, 105 and 106 there was a controversy between a Soviet laboratory and an American laboratory regarding which one had discovered them. 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.)
The USSR wanted to name element 104 after Igor Kurchatov, father of the Soviet atomic bomb, which was another reason the name was objectionable to the Americans.
The two principal groups which were involved in the conflict over element naming were:
and, as a kind of arbiter,
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.
| 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 |
The suggested names 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 |
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.
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 whatever it wanted to. Indeed, IUPAC decided that the credit for the discovery of element 106 should be shared between Berkeley and Dubna but the Dubna group had not come forward with a name.
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.
Finally in 1997, the following names were agreed on the 39th IUPAC General Assembly in Geneva, Switzerland:
Thus, the convention of the discoverer's right to name their elements was respected for elements 106 to 109,[6] and the two disputed claims were "shared" between the two opponents.
Summary of various proposals and final decision:
| Atomic number | Systematic | American | Russian | German | IUPAC 94 | Final name (IUPAC 97) |
|---|---|---|---|---|---|---|
| 104 | unnilquadium | rutherfordium | kurchatovium | — | dubnium | rutherfordium |
| 105 | unnilpentium | hahnium | nielsbohrium | — | joliotium | dubnium |
| 106 | unnilhexium | seaborgium | — | — | rutherfordium | seaborgium |
| 107 | unnilseptium | — | — | nielsbohrium | bohrium | bohrium |
| 108 | unniloctium | — | — | hassium | hahnium | hassium |
| 109 | unnilennium | — | — | meitnerium | meitnerium | meitnerium |