Scientists at Lawrence Berkeley National Laboratory are preparing to push the boundaries of the periodic table, a universal repository of chemical elements in ascending order of their atomic number. Their goal? Create unbinilium, such a heavy element that it completely defies the imagination with its 120 protonswhere gold only has 79 and lead 82. A quest that plunges us into the heart of matter and physics. Their study was published on October 21 in the journal Physical Letters.
The weight of atoms, a matter of the nucleus
The heavier an element is, the more its atomic nucleus concentrates protons and neutrons, these particles which constitute the mass of the atom, this is one of the fundamental characteristics of chemical elements. This accumulation of particles creates increasing instability: imagine an increasingly tall pyramid that threatens to collapse. This is why the heaviest natural elements, such as uranium (used in nuclear fission) with its 92 protons, are already radioactive. Beyond, each new element represents a colossal challenge to maintain even a fraction of a second this complex atomic architecture.
Radioactivity is the phenomenon by which unstable atomic nuclei spontaneously disintegrate by emitting radiation. This is why it is very difficult to create stable heavy elementsbecause the larger an atomic nucleus, the more protons and neutrons it contains which must remain glued together.
This cohesion becomes fragile in very large nuclei, since the forces which hold them together are overcome by the forces of repulsion between the protons, which are all positive, and therefore continually repel each other. This makes these heavy nuclei very unstable, and they often end up disintegrating, releasing energythat is to say by being radioactive.
A revolutionary method serving excessive ambition
The Berkeley researchers therefore imagined a unique approach to create this superheavy element: transforming titanium-50 into vapor at 1,650° C. The titanium-50 vapor thus obtained is then used to bombard other atomic elements. . In this way, they attempt to cause collisions energetic enough to fuse the nuclei of atoms and form a new, even heavier element. This technique has already made it possible to create livermorium (116 protons)a decisive first step.
By projecting this titanium beam onto californium-249, they now hope to reach the mythical number of 120 protonsthe ultimate goal of nuclear physicists. A titanic undertaking: where it took 22 days to obtain two atoms of livermorium, the creation of unbinilium could take ten times as long.
The race towards the “island of stability”
This quest goes beyond simple technical prowess or scientific fantasy. Physicists are pursuing a theoretical Holy Grail: the “island of stability”. In this predicted region of the periodic table, some superheavy elements (comprising approximately 120 protons) may exhibit unexpected stability due to particular configurations of their protons and neutrons, thereby making the element less prone to radioactive decay.
However, creating an element with 120 protons is an immense challenge. This process will require fusing very heavy atomic nuclei using particle accelerators, under extreme conditions of temperature and pressure. The Russians attempted the adventure in 2006, followed by the Germans between 2007 and 2012. Today, Americans and Chinese are joining this scientific competition which could completely change our understanding of the fundamental laws of matter.
The discovery of an element as heavy as element 120 could cconfirm or refute our theoretical models explaining the structure of matterreveal new unknown physical phenomena or help us to better understand the mechanisms of formation of elements in the universe and to retrace the history of our cosmos. Element 120 ultimately resembles the final boss ofElden Ringhe is the ultimate enemy located at the end of the periodic table, terribly unstable and complex to control.
- Berkeley scientists are attempting to create unbinilium, an element with 120 protons, via a bombardment technique with titanium-50.
- This research aims to reach the “island of stability”, where superheavy elements could be more stable than expected.
- The creation of element 120 could revolutionize our understanding of matter and test the limits of our current theoretical models.
