That oh so selective club, the Periodic Table of Elements, officially has a new member today.
Element 112, a super heavy transition metal is the second element to be added to the Table this decade. The first was Element 111, Roentgenium, which was created originally in 1994, and only 9 atoms total have ever been created. Roentgenium was added to the Table in 2001. Element 112 was originally created in 1996, but the credit for the discover was only recently assigned. The element will be called Ununbium until the team decides on an official name.
From the BBC:
More than a decade after experiments first produced a single atom of the element, a team of German scientists has been credited with its discovery.
The team, led by Sigurd Hofmann at the Centre for Heavy Ion Research, must propose a name for their find, before it can be formally added to the table.
Scientists continue the race to discover more super-heavy elements.
Professor Hofmann began his quest to add to the periodic table in 1976.
The fusion experiments he and his colleagues carried out at the centre have already revealed the existence of elements with atomic numbers 107-111.
These are known as “super-heavy elements” – their numbers represent the number of protons which, together with neutrons, give the atom the vast majority of its mass.
To create element 112, Professor Hofmann’s team used a 120m-long particle accelerator to fire a beam of charged zinc atoms (or zinc ions) at lead atoms. Nuclei of the two elements merged, or fused, to form the nucleus of the new element.
These very large and heavy nuclei are also very unstable. They begin to fall apart or “decay” very soon after being formed – within a few milliseconds, in this case.
This releases energy, which scientists can measure to find out the size of the decaying nucleus.
But such experiments produce very few successful fusions, and scientists need increasingly powerful accelerators to run experiments for longer and find the elusive, unstable elements.
This is why it took such a long time for element 112 to be officially recognised by the International Union of Pure and Applied Chemistry (IUPAC).
Its discovery had to be independently verified, and so far only four atoms have ever been observed.