Kröger–Vink notation

Kröger–Vink notation is a set of conventions that are used to describe electric charges and lattice positions of point defect species in crystals.

It was proposed by Ferdinand Anne Kröger [fr] and Hendrik Jan Vink [nl].

The first step in this process is determining the correct type of defect and reaction that comes along with it; Schottky and Frenkel defects begin with a null reactant (∅) and produce either cation and anion vacancies (Schottky) or cation/anion vacancies and interstitials (Frenkel).

The following oxidation–reduction tree for a simple ionic compound, AX, where A is a cation and X is an anion, summarizes the various ways in which intrinsic defects can form.

From the chart above, there are total of four possible chemical reactions using Kröger–Vink Notation depending on the intrinsic deficiency of atoms within the material.