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Alfred Nobel, known for discovering dynamite and establishing the Nobel Prizes, has an element named after him: nobelium. Discovered in 1957, its discovery was controversial, but the name nobelium was eventually chosen to honor Nobel. Nobelium has 17 isotopes, with Nobelium-259 being the most stable. Its discovery and isotopes have been the subject of controversy.
Alfred Nobel, a Swedish chemist who lived from 1833 to 1896, is known for discovering dynamite and for using his fortune to establish the prestigious group of prize winners known as the Nobel Prizes. It is less known that the synthetic element with atomic number 102, nobelium, is named after him. Nobelium was discovered in 1957, the penultimate of the transuranic actinoids to be discovered.
The discovery of nobelium has an interesting story. Its discovery was announced in 1957 by physicists from the Nobel Institute in Sweden. The discovery was made following the bombardment of curium with carbon nuclei, and confirmed in several other laboratories, under the proposed name nobelium. But then the results were withdrawn. In 1958, a team from the University of California at Berkeley tried again, this time using carbon ions, and although they were unable to confirm previous reports, they were eventually able to produce an isotope of 102.
The team of Albert Ghiorso, Glenn T. Seaborg, Torbjørn Sikkeland and John R. Walton – given the choice of name – suggested that the original designation of nobelium and No stand, and so it was. But a more recent investigation in 1992 showed that while the Berkeley team may have detected element 102, the first definitive detection was at Dubna in 1966, and the International Union of Pure and Applied Chemistry (IUPAC) recognizes scientists from Dubna as discoverers.
Dubna scientists proposed the name Joliotium with the symbol Jo in recognition of Frédéric Joliot-Curie, but this name was not used. For a short time, the name flerovium with the atomic symbol Fl was used at the suggestion of the IUPAC to refer to the element. But this was superseded by IUPAC’s acknowledgment that the name nobelium, having been used for 30 years, was pervasive throughout literature and should be retained, both for that reason and to honor Alfred Nobel.
Nobelium was synthesized from the decay of heavier elements, including Hassium, Lawrencium, Rutherfordium and Seaborgium. However, there are insufficient quantities of nobelium to create a radiation hazard – which it would in sufficient quantities – or to describe such things as its appearance.
Seventeen isotopes have been described, with the most stable – Nobelium-259 – having a half-life of 58 minutes. Other isotopes are expected to have longer half-lives. The controversies surrounding its original discovery have extended to the discovery of its isotopes. The 2003 claim by Flerov Nuclear Reaction Laboratory (FLNR) scientists that they had found the lightest known isotope to date was retracted, when the Nobelium-249 indications were found to have been caused by Nobelium-250.
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