Monument commemorating the discovery of nihonium at the west gate to the Riken institute in Wako, Japan
29 March 2024
Nihonium is a synthetic chemical element with atomic number 113 and the symbol Nh. The half-life of its longest-lived isotope is measured in seconds. It has no applications beyond pure research.
The element was first reported to have been produced in 2003 at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia as part of a collaboration with Lawrence Livermore National Laboratory (LLNL) in the United States. The JINR-LLNL team published their finding in February 2004. But in October 2004, scientists at the Riken institute in Japan published a more detailed report on work they had been conducting on element 113.
It took until 2016 for the International Union of Pure and Applied Chemistry (IUPAC) to resolve the dispute over which group had priority in the discovery. IUPAC decided that the Japanese group had priority and announced this preliminary finding, along with the assignment of the name nihonium, in a press release dated 8 June 2016:
For the element with atomic number 113 the discoverers at RIKEN Nishina Center for Accelerator-Based Science (Japan) proposed the name nihonium and the symbol Nh. Nihon is one of the two ways to say “Japan” in Japanese, and literally mean “the Land of Rising Sun”. The name is proposed to make a direct connection to the nation where the element was discovered. Element 113 is the first element to have been discovered in an Asian country.
IUPAC finalized its decision in December 2016.
IUPAC guidelines formulated in 2016 require new elements be named after either a mythological character or concept (or an astronomical object named after such a mythological concept), a mineral, a place, or a scientist. Elements in columns 1–16 of the periodic table take the usual suffix -ium. Those in column 17 take the suffix -ine, and those in column 18 the suffix -on. Nihonium is in column 13, hence the -ium ending. Of course, older names for elements may not conform to these guidelines.
Sources:
International Union of Pure and Applied Chemistry (IUPAC). “IUPAC Is Naming the Four New Elements Nihonium, Moscovium, Tennessine, and Oganesson (press release), 8 June 2016.
Joint Institute for Nuclear Research (JINR). “Discovery of the New Chemical Elements with Numbers 113, 115, 117 and 118” (press release), 6 January 2016.
Miśkowiec, Pawel. “Name Game: The Naming History of the Chemical Elements—Part 3—Rivalry of Scientists in the Twentieth Century.” Foundations of Chemistry, 12 November 2022. DOI: 10.1007/s10698-022-09452-9.
Morita, Kosuke, et al. “Experiment on the Synthesis of Element 113” (30 July 2004). Journal of the Physical Society of Japan, 73.10, October 2004, 2593–96. DOI: 10.1143/JPSJ.73.2593.
Oganessian, Yu. Ts., et al. “Experiments on the Synthesis of Element 115.” Physical Review C, 69, 2 February 2004, 021601-1–5. American Physical Society.