Back to Periodic Table
Actinides

Lawrencium

The final actinide, fleeting and entirely synthetic.

Atomic #103Mass[266]Blockf-blockPeriod7Group
Lr103 · [266]
3D Atom Explorer

Inside the Lawrencium atom

Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Lawrencium atom step by step.

Loading 3D atom…

Electron configuration

[Rn] 5f14 7s2 7p1

A neutral Lawrencium atom has 103 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.

Shell distribution

Shell 12 e⁻Shell 28 e⁻Shell 318 e⁻Shell 432 e⁻Shell 532 e⁻Shell 68 e⁻Shell 73 e⁻

Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.

Properties

Physical & atomic properties

State (room temp)
Unknown
Melting point
1900 K (1627 °C)
Boiling point
Density
Electronegativity
Atomic radius
1st ionization energy
479 kJ/mol
Category
Actinides
History

Discovery & naming

Discovered
1961
Discovered by
Berkeley and Dubna teams
Origin of name
Physicist Ernest Lawrence.

Notable uses

Scientific research only.

Cosmic origin

Where Lawrencium comes from

Human synthesis

Synthetic and short-lived, made by fusing light ions with californium.

Simplified origin map — many elements form through more than one astrophysical pathway.

Summary

Atomic number
103
Atomic mass
[266]
Category
Actinides
Group · Period
— · 7
Block
f-block
Shells
2 · 8 · 18 · 32 · 32 · 8 · 3