Copernicium Cn

Discovery

On 9 February 1996 Sigurd Hofmann's team at GSI bombarded lead-208 with zinc-70 ions and detected a single atom of element 112, copernicium-277. After further GSI experiments in 2000 and a confirmation at Japan's RIKEN in 2004, the joint IUPAC–IUPAP working party officially recognised GSI as the discoverer in 2009.

In July 2009 GSI proposed Copernicus's name with the symbol Cp. That symbol, however, had once been used for 'cassiopeium', an old name for lutetium, and has other meanings in chemistry, so it was changed to Cn. The name was formally announced on 19 February 2010, Copernicus's birthday.

Origin of the name

The element honours Nicolaus Copernicus, the Polish astronomer whose heliocentric model transformed our view of the universe. The team also noted the resemblance between electrons circling a nucleus and planets circling the Sun. The symbol is Cn.

Main uses

• Basic research: It has no uses outside science.
• Chemistry: Around 2007, experiments adsorbing single atoms onto gold surfaces showed copernicium behaving like mercury but even more volatile. Some predictions suggest that relativistic effects bind its outer electrons so tightly that it could behave almost like a noble gas, making it a central target of superheavy chemistry.

Isotopes

There are no stable isotopes. The longest-lived, copernicium-285, has a half-life of about 30 seconds and was observed in the decay chain of element 114, flerovium. Copernicium-277, the discovery isotope, lasts less than a millisecond.

In everyday life

It does not exist in nature; only a few atoms at a time are made in accelerators and they decay almost immediately, so it has no connection with daily life or health.