Copernicium

Copernicium (Copernicium, symbol: Cn) is a chemical element with atomic number 112. It is a synthetic element—it does not occur naturally on Earth, but is created in the laboratory using a particle accelerator. It belongs to the class of superheavy elements.

The element is named after the astronomer Nicolaus Copernicus. Like other heavy elements, atoms of Cn produced this way are extremely rare—only a few atoms at a time—and decay very quickly (radioactive decay), which makes it difficult to measure its chemical properties directly.

Discovery

It was first synthesized at the GSI heavy-ion research center in Darmstadt, Germany, by a team led by Sigurd Hofmann and Peter Armbruster in collaboration with Gottfried Münzenberg. The method is a nuclear fusion collision: a heavy lead nucleus is bombarded with a nickel target, producing a new nucleus that is observed only once. Official recognition of the element and its name was assigned by IUPAC (International Union of Pure and Applied Chemistry) only after a considerable delay.

Properties

In the periodic table, Cn occupies group 12, alongside zinc (Zn), cadmium (Cd), and mercury (Hg). The electron configuration suggests it should naturally resemble mercury. However, relativistic effects—the influence of high-speed electrons deep within the atom—are expected to alter its behavior. Some researchers have proposed that it may behave as a noble gas or as a very soft metal. Experiments on small quantities have attempted to measure how it interacts with a gold surface.

Isotopes and decay

All isotopes of Cn are radioactive. Their half-lives range from fractions of a millisecond to several milliseconds for the most stable isotopes. The dominant decay mode is alpha emission and occasionally spontaneous fission. For this reason, Cn has no commercial or industrial application; it is used only in nuclear research and in studying the limits of the periodic table.