Interstitial Defect

Interstitial Defect

Interstitials are a variety of crystallographic defects, i.e. atoms which occupy a site in the crystal structure at which there is usually not an atom, or two or more atoms sharing one or more lattice sites such that the number of atoms is larger than the number of lattice sites. They are generally high energy configurations. Small atoms in some crystals can occupy interstitial sites in an energetically favourable configuration, such as hydrogen in palladium. Interstitials can be produced for instance by particle irradiation above the threshold displacement energy, but may also exist in small concentrations in thermodynamic equilibrium.