Nobelium

Nobelium carries the name of Alfred Nobel, the Swedish inventor of dynamite and founder of the Nobel Prizes — yet the story of its discovery is anything but peaceful. Its identification became one of the most contentious priority disputes in the history of nuclear chemistry, with competing teams on opposite sides of the Cold War each claiming credit for the same element. The truth, as is often the case, turned out to be complicated.

Nobelium has no practical applications of any kind. It is produced in quantities of individual atoms, decays within minutes to hours, and can only be studied using the most sensitive radiation-detection instruments available. All research involving nobelium is purely fundamental, aimed at understanding the nuclear structure and chemistry of the heaviest actinide elements before the periodic table transitions into the transactinide series.

In 1957, a team at the Nobel Institute in Stockholm announced the discovery of element 102 and proposed the name nobelium. Their results could not be reproduced and were later retracted. Soviet scientists at the Joint Institute for Nuclear Research in Dubna, led by Georgy Flerov, conducted extensive experiments throughout the early 1960s and confirmed the element's existence. A Berkeley team under Albert Ghiorso also confirmed it independently in 1966. Despite the original Stockholm claim being discredited, the IUPAC ultimately retained the name nobelium — a decision that frustrated the Dubna team, who had proposed the name joliotium.

Nobelium does not exist in nature and has never been found in any terrestrial or extraterrestrial sample. Every atom must be created by bombarding a heavy-element target — typically curium — with accelerated carbon or other ions inside a particle accelerator. The amounts produced in any experiment are measured in single atoms.

Research into nobelium's chemistry is severely limited by its short half-lives and tiny production yields. Studies in aqueous solution have revealed a surprising result: nobelium tends to favor the +2 oxidation state rather than the +3 state common to most actinides. This anomalous stability of No2+ is attributed to the element's electron configuration and makes it chemically distinct from its actinide neighbors.

• The Nobel Institute's original 1957 claim of discovering element 102 was eventually retracted after other laboratories could not reproduce the results — a rare and embarrassing reversal in nuclear science.
• Despite the Soviet team doing the most to confirm nobelium's existence, the name proposed by the discredited Stockholm group stuck, a decision that remained a sore point in the USSR for years.
• Nobelium favors the +2 oxidation state in solution, which is unusual for actinides and reflects a particularly stable electron configuration at this position in the periodic table.
• The most stable isotope, No-259, has a half-life of just 58 minutes, meaning any sample produced in an accelerator is essentially gone before most laboratory procedures could even begin.
• Nobelium is the second-to-last actinide, sitting just before lawrencium, which closes the f-block of the periodic table.