A newcomer to the periodic table

The newest element in the periodic table, atomic number 112, has been granted a chemical symbol, more than 10 years after it was first discovered, according to a report in New Scientist.

The International Union for Pure and Applied Chemistry has approved the name copernicium and the chemical symbol Cn for the highest numbered officially recognised element. It rejected the original suggestion of Cp to avoid confusion because before 1949 Cp referred to cassiopeium (atomic number 71), which is now known as lutetium and has the symbol Lu.

Copernicium was so named by its discoverer, Sigurd Hofmann, after Copernicus, the father of the heliocentric solar system. It had previously been known only under its IUPAC systematic element name of ununbium. It joins a growing list of elements that have been named after scientists. They include einsteinium, after Albert Einstein, curium, after Marie and Pierre Curie, and rutherfordium, after Ernest Rutherford.

Elements have also commonly been named after mythical characters (such as iridium, after Iris, the Greek goddess of the rainbow), places (such as polonium, after Polonia, the Latin for Poland) and astronomical objects (eg, tellurium, after Tellus, Latin for Earth).

Element 112 is the sixth to be discovered by the Centre for Heavy Ion Research (GSI) in Darmstadt, Germany. The previous five are bohrium (107), hassium (108), meitnerium (109), darmstadtium (110) and roentgenium (111).

Copernicium is tucked away in the bottom right hand corner of the periodic table, where scientists are extending the table beyond the heaviest naturally occurring element, uranium (atomic number 92). Elements 113, 114, 116 and 118 have still to be officially approved by IUPAC.

Only about 75 atoms of copernicium have been detected using various nuclear reactions. The most stable isotope of this radioactive transition metal has a half-life of about 30 seconds.

Hofmann’s team first created the element in 1996 by firing accelerated zinc nuclei at a lead target in a heavy ion accelerator, producing a single atom of the new element.