Element 117 could be latest addition to periodic table
By fusing calcium and berkelium, researchers have produced a new super-heavy element with 117 protons.
G. Otto, GSI Helmholtz Center for Heavy Ion Research
Your next periodic table might have a new entry: A team of scientists in Germany have produced an element with 117 protons, making it the second-heaviest element ever created by humans after ununoctium, or element 118.
Temporarily named "Ununseptium" to denote its atomic number 117, the element was produced by accelerating ions of calcium (which has 20 protons) into a target of berkelium (which has 97).
Scientists at the Oak Ridge National Laboratory in the United States synthetically produced the berkelium used in the experiment, which was then shipped, in powdered form, to Mainz University in Germany, where researchers converted the powder into chemically stable thin layer. This was then deposited on a titanium foil that was used as a target for the test.
The experiment, carried out by an international team of researchers at the GSI Helmholtz Center for Heavy Ion Research, resulted in the production of "two atoms of the superheavy element with atomic number Z=117, confirming the initial observation published in 2010," researchers noted in their synopsis.
The ununseptium was observed to have a half-life of 50 milliseconds, or one twentieth of a second, says Christoph Düllmann of GSI, Johannes Gutenberg University Mainz (JGU) and the Helmholtz Institute Mainz (HIM), who carried out the study along with his team.
It gradually decayed into lighter elements, emitting alpha particles (a helium nuclei with two protons and two neutrons) in the process. And the lighter elements formed have a greater half-life than ununseptium, Dr. Düllmann told the Monitor.
The newly created element's half-life was too short for it to be chemically studied, but after examining the alpha particles, researchers concluded that the original element indeed had an atomic number 117.
Düllmann says that even though ununseptium has a very short half-life, it qualifies as an element because within that short time it has the capability of "arranging its electronic shell." In other words, it can arrange 117 electrons within a fraction of a second. The new element has 117 protons and 177 neutrons, says Düllmann.
The findings of the study will now be reviewed by the International Unions of Pure and Applied Physics and Chemistry. And if ununseptium qualifies as an element, it will be the second heaviest element in the periodic table after ununoctium, or element 118.
"The successful experiments on element 117 are an important step on the path to the production and detection of elements situated on the 'island of stability' of superheavy elements," Horst Stöcker, Scientific Director of GSI said in a press release.
Various researchers are trying to produce elements with an atomic number of 119. Elements beyond atomic number 104 are referred to as super-heavy elements.
The findings of the study have been published in the journal Physical Review Letters.