Copernicium (Cn)

Isotopes of Copernicium 

Isotope Atomic Mass Half-life Mode of Decay Nuclear Spin Nuclear Magnetic Moment
Cn-277 277 0.00024 seconds α to Ds-273 No data available  No data available 
Cn-283 283 3.00 minutes SF No data available  No data available 
Cn-284 284 44.30 seconds α to Ds-280 No data available  No data available 
Cn-285 285 11.00 minutes α to Ds-281 No data available  No data available 


Copernicium is an extremely radioactive synthetic element that can only be created in a laboratory. It was discovered in 1996 at Gesellschaft für Schwerionenforschung (GSI) (Center for Heavy Ion Research) in Darmstadt, Germany, by a team of scientists led by Sigurd Hofmann. The new element was produced by fusing a zinc atom with a lead atom. Temporarily labeled "ununbium" (un meaning "one" and bi meaning "two," referring to the element's atomic number, 112), copernicium officially received its permanent name — proposed in honor of scientist and astronomer Nicolaus Copernicus — on February 19, 2010, the 537th anniversary of Copernicus' birth.

In total, approximately 75 atoms of copernicium have been detected using various nuclear reactions. It has no stable or naturally-occurring isotopes, although several radioactive isotopes have been synthesized in the laboratory, either by fusing two atoms or by observing the decay of heavier elements. During reactions with gold, it has been shown to be an extremely volatile metal. The isotope Copernicium-283 was instrumental in the confirmation of the discoveries of the elements flerovium and livermorium.

Properties of Copernicium

Name Copernicium
Symbol Cn
Atomic number 112
Atomic weight [285]
Standard state Presumably a liquid at 298 °K
CAS Registry ID 54084-26-3
Group in periodic table 12
Group name None
Period in periodic table 7
Block in periodic table d-block
Color Unknown, but probably metallic and silvery white or grey in appearance
Classification Metallic
Melting point No data available
Boiling point No data available
Density of solid 16.8 g/cm3 (predicted)
Ground state electron configuration [Rn]5f146d107s2 (predicted)

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