Selenium • Non-Metals

Primary XPS region: Se3d
Overlapping regions: Li1s, Mg2p
Binding energies of common chemical states:

Chemical stateBinding energy Se3d5/2/eV
Se metal55.1

Experimental Information


Interpretation of XPS spectra

  • Se3d peak has overlapping spin-orbit components (Δ=0.86 eV, intensity ratio=0.735).
    • Loss feature located at 58.5 eV, visible in Se3d spectrum for metal.
  • Se LMM peaks (between 150eV–400eV) overlap with many XPS peaks from other elements and selenium’s own XPS peaks.

About This Element

Symbol: Se
Date of Discovery: 1817
Name Origin: Greek Selênê
Melting Point: 4904 K
Boiling Point: 958 K
Density[kg/m3]: 4819
Molar Volume: 16.42 × 10-6 m3/mol
Protons/Electrons: 34
Appearance: gray
Discoverer: Jöns Berzelius
Obtained From: refining of lead, copper, nickel
Neutrons: 45
Shell Structure: 2,8,18,6
Electron Configuration: [Ar]3d104s24p4
Oxidation State: ±2,4,6
Crystal Structure: monoclinic, hexagonal 

Selenium was discovered by Jöns Jakob Berzelius 1817 and derives its name from the Greek word “selene”, meaning moon. Although selenium is naturally found in a few rare minerals, it is primarily produced as a byproduct of copper refining. Selenium exists in two crystalline forms: crystalline monoclinic selenium is a deep red, while crystalline hexagonal selenium, the most stable form, is metallic gray. Selenium’s photovoltaic and photoconductive properties contribute to its use in photocopying, toning of photographic prints, photocells, light meters, and solar cells. A semi-conductive material below its melting point, selenium is also used in electronic applications.


Application Notes

Return to Elements Table