Copernicium: the essentials
Copernicium was discovered on 9th February 1996 at 22:37 at the GSI in Darmstadt, Germany. Further information on element 112 is here (outside WebElements) and here in a press release (outside WebElements). The interested reader should consult the on-line version of The Wonderful World of Atoms and Nuclei for a fascinating insight into research on "super-heavy" atoms.
In honour of scientist and astronomer Nicolaus Copernicus (1473-1543), the discovering team around Professor Sigurd Hofmann suggested the name copernicium with the element symbol Cn (the original proposal was Cp) for the new element 112, discovered at the GSI Helmholtzzentrum für Schwerionenforschung (Center for Heavy Ion Research) in Darmstadt. It was Copernicus who discovered that the Earth orbits the Sun, thus paving the way for our modern view of the world. Thirteen years ago, element 112 was discovered by an international team of scientists at the GSI accelerator facility. A few weeks ago, the International Union of Pure and Applied Chemistry, IUPAC, officially confirmed their discovery. In around six months, IUPAC will officially endorse the new element's name. This period is set to allow the scientific community to discuss the suggested name copernicium before the IUPAC naming.
Copernicium: historical information
Element 112 (provisionally named copernicium, Cn) was discovered on 9th February 1996 at 22:37 at the GSI in Darmstadt, Germany. The identified isotope currently is the heaviest atom ever produced by man and has an atomic mass of 277, that is, 277 times heavier than hydrogen. The new element was produced by fusing a zinc atom with a lead atom. To achieve this, the zinc atom was accelerated to high energies by the heavy ion accelerator UNILAC at GSI and directed onto a lead target.
Copernicium: physical properties
Copernicium: orbital properties
Isolation: as only a few atoms of element 112 (provisionally named copernicium, Cn) have ever been made (through a nuclear reaction involving fusing a zinc atom with a lead atom) isolation of an observable quantity has never been achieved, and may well never be.
208Pb + 70Zn → 277Cn + 1n This is because atoms of the element decompose through the emission of α-particles with a half life of only about 240 microseconds. Abstract (http://www.gsi.de/forschung/kp/kp2/ship/public/sn112-abstract.html ): The new element 112 (provisionally named copernicium, Cn) was produced and identified unambiguously in an experiment at SHIP, GSI Darmstadt. Two decay chains of the isotope 277-112 were observed in irradiations of 208-Pb targets with 70-Zn projectiles of 343.8 MeV kinetic energy. The isotope decays by emission of alpha particles with a half-life of (240 +430 -90) micro seconds. Two different alpha-energies of (11,649+-20)keV and (11,454+-20) keV) were measured for the decaying nuclei. The cross section measured in three weeks of irradiation is (1.0 +1.3 -0.6) pb.
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