Flerovium (Fl)

Flerovium (symbol Fl) is the chemical element with atomic number 114: a superheavy element whose properties are still unknown, radioactive, made artificially, with an atomic mass of 289 u. Discovered in 1998 (Yuri Oganessian et al. (Dubna)).

Flerovium, named after the Flerov Laboratory in Dubna (itself named for physicist Georgy Flerov), was created in 1998–1999. It fascinates physicists because 114 was predicted to be a “magic” number of protons, close to a hypothetical “island of stability”: a region where superheavy nuclei would live much longer than their neighbors. Its most stable known isotope lives a few seconds, which is long for such a heavy element.

Key facts

Atomic number: 114
Symbol: Fl
French name: Flérovium
Atomic mass: 289 u
Molar mass: [289] g/mol
Family: Unknown properties
Position: period 7, group 14, p-block
State at 0 °C: Unknown
First ionization energy: 832 kJ/mol
Electron configuration: [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p²
Radioactive: yes
Discovery: 1998, Yuri Oganessian et al. (Dubna)

Origin of the name

From the Flerov Laboratory in Dubna, named after Georgy Flerov.

What does flerovium look like?

Never observed. Experiments on a few atoms suggest a highly volatile, barely reactive metal — unexpected behavior for a cousin of lead.

Where is flerovium found?

Absent from nature.

How is flerovium produced?

Dubna bombards a plutonium-244 target with calcium-48 ions. This very special calcium, which makes up just 0.2% of natural calcium, is neutron-rich: it yields nuclei closer to the island of stability. This is known as “hot fusion”: the nucleus formed is more excited and sheds several neutrons.

Top producers

Russia (Dubna)
United States (Livermore, collaborator)
Germany (GSI)

What is flerovium used for?

Basic research only
Searching for the island of stability of superheavy nuclei

In everyday life

None — it exists only for moments in the lab

Role in living things

No biological role.

Hazards of flerovium

Radioactive, but produced atom by atom: no practical danger.

Cosmic origin

Human-made: Does not exist (or barely) in nature: synthesized in a reactor or accelerator.

History of flerovium

In December 1998, Yuri Oganessian's team in Dubna, working with Lawrence Livermore National Laboratory, observed a first event; reproducible observations followed in 1999 and the years after. IUPAC recognized the discovery in 2011, and the name flerovium was adopted in 2012.

Did you know?

The “island of stability” is an idea from the 1960s: beyond a sea of unstable nuclei, some superheavy nuclei might live for minutes, or even much longer. Scientists are getting closer without having reached it.
The very first atom observed in 1998 seemed to live about thirty seconds, a lifetime never seen again since; its nature is still debated.
It was named on the same day as livermorium, in 2012.

Isotopes of flerovium

No stable isotopes; flerovium lies close to the “island of stability” predicted by physicists, yet its isotopes live only a few seconds.

flerovium-288: radioactive, half-life 650 ms
flerovium-289: radioactive, half-life 1.9 s. The longest-lived known; the first isotope observed, in 1998 in Dubna.

Related elements

Same family (unknown properties): Meitnerium (Mt), Darmstadtium (Ds), Roentgenium (Rg), Copernicium (Cn), Nihonium (Nh), Moscovium (Mc), Livermorium (Lv), Tennessine (Ts), Oganesson (Og).

Same column (group 14): Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn), Lead (Pb).