Impurity Interstitials
Small impurity interstitial atoms are usually on true off-lattice sites between the lattice atoms. Such sites can be characterized by the symmetry of the interstitial atom position with respect to its nearest lattice atoms. For instance, an impurity atom I with 4 nearest lattice atom A neighbours (at equal distances) in a FCC lattice is in a tetrahedral symmetry position, and thus can be called a tetrahedral interstitial.
Large impurity interstitials can also be in split interstitial configurations together with a lattice atom, similar to those of the self-interstitial atom.
Read more about this topic: Interstitial Defect
Famous quotes containing the word impurity:
“Purity is not imposed upon us as though it were a kind of punishment, it is one of those mysterious but obvious conditions of that supernatural knowledge of ourselves in the Divine, which we speak of as faith. Impurity does not destroy this knowledge, it slays our need for it.”
—Georges Bernanos (1888–1948)