Lanthanides
Erbium
A rare earth that amplifies signals in fiber-optic cables.
Atomic #68Mass167.26Blockf-blockPeriod6Group—
Er68 · 167.26
3D Atom Explorer
Inside the Erbium 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 Erbium atom step by step.
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Electron configuration
[Xe] 4f12 6s2
A neutral Erbium atom has 68 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 430 e⁻Shell 58 e⁻Shell 62 e⁻
Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.
Properties
Physical & atomic properties
- State (room temp)
- Solid
- Melting point
- 1802 K (1529 °C)
- Boiling point
- 3141 K (2868 °C)
- Density
- 9.066 g/cm³
- Electronegativity
- 1.24 Pauling
- Atomic radius
- 175 pm
- 1st ionization energy
- 589 kJ/mol
- Category
- Lanthanides
History
Discovery & naming
- Discovered
- 1843
- Discovered by
- Carl Gustaf Mosander
- Origin of name
- Ytterby, a village in Sweden.
Notable uses
Fibre-optic amplifiers and pink-tinted glass.
Cosmic origin
Where Erbium comes from
Neutron star mergers
Chiefly built by rapid neutron capture rather than by slow capture in quiet stars.
Simplified origin map — many elements form through more than one astrophysical pathway.
Summary
- Atomic number
- 68
- Atomic mass
- 167.26
- Category
- Lanthanides
- Group · Period
- — · 6
- Block
- f-block
- Shells
- 2 · 8 · 18 · 30 · 8 · 2