text: Interstitials modify the physical and chemical properties of materials.
  * Interstitial carbon atoms have a crucial role for the properties and processing of steels, in particular carbon steels.
  * Impurity interstitials can be used e.g. for storage of hydrogen in metals.
  * The crystal lattice can expand with the concentration of impurity interstitials
  * The amorphization of semiconductors such as silicon during ion irradiation is often explained by the build up of a high concentration of interstitials leading eventually to the collapse of the lattice as it becomes unstable.
  * Creation of large amounts of interstitials in a solid can lead to a significant energy buildup, which on release can even lead to severe accidents in certain old types of nuclear reactors (Wigner effect). The high-energy states can be released by annealing.
  * At least in fcc lattice, interstitials have a large diaelastic softening effect on the material.
  * It has been proposed that interstitials are related to the onset of melting and the glass transition.