ELEMENTLE

Element 115 · Metal

Moscovium

Period 7 · Group 15

Moscovium is the name of a synthetic superheavy element in the periodic table that has the symbol Mc and has the atomic number 115. It is an extremely radioactive element; its most stable known isotope, moscovium-289, has a half-life of only 220 milliseconds. It is also known as eka-bismuth or simply element 115.

Three reasons Moscovium stands out

  1. 1

    Synthetic element, named after the capital of Russia.

  2. 2

    It was first synthesised in 2003 by bombarding another heavy element with calcium nuclei in a heavy-ion accelerator.

  3. 3

    Each atom produced decays within a fraction of a second, leaving almost no time to study its properties.

A Moscow-region name built from calcium collisions

Moscovium was produced by firing calcium-48 nuclei into americium targets, then identifying linked radioactive decays. Its name honors Moscow Oblast, where the Dubna laboratory is located. Chemistry is largely predicted, with relativistic effects expected to complicate its resemblance to bismuth.

Moscovium at a glance
Atomic number / protons115
SymbolMc
Family (Elementle)Metal
Classification (PubChem)Post-transition metal
Period7
Group15
Atomic mass (u)290.196
Standard stateBulk state not experimentally established
Electron configuration[Rn]7s2 7p3 5f14 6d10 (predicted)
Reported oxidation states3, 1
Electronegativity (Pauling)Not available
Atomic radius (pm)Not available
First ionization energy (eV)Not available
Electron affinity (eV)Not available
Density (g/cm³)Not available
Melting pointNot available
Boiling pointNot available
Discovery (PubChem)2003

Values are reference data, not a specification for every temperature, pressure, or allotrope. Unknown properties are left unavailable. Superheavy-element predictions remain uncertain.

Sources & further reading

PubChem: Moscovium · Moscovium on Wikipedia

The introduction and original editorial story are adapted from Wikipedia contributors via Periodic-Table-JSON. Element descriptions and their adaptations are available under CC BY-SA 3.0. Numerical attributes use the PubChem periodic-table dataset, retrieved September 22, 2026.