Nihonium · element 113
The first element discovered in Asia took nine years, a linear accelerator and just three atoms to prove
Key facts
Nihonium is Japan's element. Its name comes from Nihon, a Japanese word for Japan meaning the land of the rising sun. It was made at the RIKEN laboratory near Tokyo by a team led by Kosuke Morita, and it is the first element discovered and named in Asia. It also settled an old score: in 1908 the chemist Masataka Ogawa had announced a Japanese element, nipponium, which turned out to be a misidentification.
Element 113 sits under thallium in group 13. It is a slippery thing to make. RIKEN's reaction produced one atom in 2004, one in 2005 and a third in 2012, and that seven-year gap tells you everything about how rare a successful fusion is.
Where it is found
Nihonium is not found in nature. Its most stable isotope survives for around ten seconds, so it cannot have persisted from any cosmic event. All of it has been made in accelerators, with a total in the low hundreds if you count the nuclei that appear briefly as decay products of moscovium.
RIKEN used cold fusion, firing zinc-70 ions at a bismuth-209 target for months at a time. Fusions are so rare that the team ran the accelerator for the equivalent of years to catch three atoms of nihonium-278. Dubna instead fires calcium-48 at americium-243 to make moscovium, which emits an alpha particle and becomes nihonium-284 or 286. That indirect route yields nihonium far more often and gives longer-lived isotopes, which chemists prefer.
How it was discovered
Two laboratories were involved and the question of credit was subtle. In 2003 and 2004 the Dubna and Livermore collaboration reported moscovium decaying to nihonium, but their decay chains ended in isotopes nobody had seen before, so there was no anchor to known nuclei. RIKEN's approach was harder but cleaner. Their third atom, in August 2012, gave a chain of six alpha decays ending in mendelevium-254, a well-charted nucleus.
In December 2015 IUPAC awarded the discovery to RIKEN, largely because of that unambiguous chain. The team proposed nihonium, and the name was approved in November 2016 along with moscovium, tennessine and oganesson, completing the seventh row of the periodic table. Morita has described the element as a gift to Japan and a thank-you to the public for supporting basic research.
What we use it for
Nihonium has no practical uses. Its interest lies in chemistry that is only just becoming possible. Nihonium-286, from moscovium decay, lives for around ten seconds, enough for the gas-phase techniques used on lighter superheavy elements.
The first attempts were made at Dubna in 2017. Nihonium atoms were carried along channels lined with Teflon and gold to see where they stuck. The results were puzzling: nihonium seemed less volatile than predicted and clung to surfaces more strongly than expected, possibly because it forms a hydroxide. Theorists predict a preference for +1, like thallium, because relativity splits the 7p shell and makes one electron especially easy to remove. Whether nihonium is a heavy thallium or something stranger is what future experiments aim to settle.
Reading the numbers
The atomic mass of 286 is the longest-lived isotope. The other figures are predictions. A melting point of about 700 kelvin, roughly 430 degrees Celsius, and a boiling point around 1430 kelvin, about 1160 degrees Celsius, would make nihonium a fairly low-melting metal, normal for its group. The predicted density of about 16 grams per cubic centimetre is above thallium's 11.9. None of this has been measured, because a visible sample has never existed.
The configuration [Rn] 5f14 6d10 7s2 7p1 puts one electron in the 7p shell, which is why nihonium is in group 13 and is the first p-block element of period 7. Relativity makes the 7s pair hard to involve in bonding, so +1 is expected to dominate and +3 to be rare. The surprise so far is that nihonium may be less volatile and more reactive towards surfaces than a simple extrapolation from thallium would suggest.
Safety and the environment
Nihonium is radioactive and short-lived, with half-lives from milliseconds to around ten seconds. It cannot be stockpiled, shipped or released. The few hundred atoms ever made were produced inside shielded accelerators and detected through their own decay. There is no nihonium in the environment and no way for the public to encounter it.
Did you know?
- RIKEN detected just three atoms of nihonium-278 in total: one in 2004, one in 2005 and one in 2012.
- The bismuth-209 target used to make nihonium is itself very faintly radioactive, with a half-life about a billion times the current age of the universe.
- In 1908 the Japanese chemist Masataka Ogawa claimed a new element he named nipponium; it was later concluded he had probably found rhenium, which was not officially discovered until 1925.
- Nihonium is the first element in period 7 to have an electron in a p orbital, making it the first p-block element of the seventh row.
- Nihonium was one of four elements named on the same day in November 2016, completing the seventh row of the periodic table.
More in the superheavy elements
The nearest neighbours of nihonium in the family, by atomic number.
See all 15 superheavy elements on one page, or browse all 118 elements. Also listed under the post-transition metals.
Frequently asked questions
Why is nihonium called nihonium?
The name comes from Nihon, a Japanese word for Japan meaning land of the rising sun. It was chosen by the RIKEN team that discovered the element and approved by IUPAC in November 2016. It is the first element named for an Asian country.
Who discovered nihonium?
A team at RIKEN in Japan led by Kosuke Morita was credited with the discovery in 2015. A Dubna and Livermore collaboration had observed nihonium earlier as a decay product of moscovium, but the RIKEN evidence was judged more conclusive.
What is the half-life of nihonium?
It depends on the isotope. Nihonium-278, made at RIKEN, lasts a few thousandths of a second. Nihonium-286, produced from moscovium decay, survives for roughly ten seconds.
Is nihonium a metal?
It is expected to be a metal similar to thallium, with a relatively low melting point and a preferred +1 oxidation state. Early chemistry experiments suggest it may be less volatile than predicted, but the results are still being interpreted.
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Written by Anthony. Updated September 2026. Numerical data from Periodic-Table-JSON (CC BY-SA), cross-checked against the Nihonium reference article. Spotted an error? Tell us.