In which defect equal number of cations and anions are missing from their lattice position?

Defects/ Imperfections

Types of Defects / Imperfection

Point defects

(Zero-dimensional)

Vacancy Defect: It appears due to the missing of an atom from the lattice.

Frenkel defect: Atom occupies interstitial void in the lattice.

Schottky defect: It appears if, in a combination of cation and anion there is a vacancy.

Interstitial defect: It appears when a foreign atom occupies the interstitial site

Substitutional defect: It appears if a regular atom is replaced by another foreign atom.

Line defect or dislocations

(One-Dimensional)

Edge dislocation: If force is applied on 50% area and exceeds beyond a certain limit slipping of plane happens and an extra half-plane appears at dislocation line.

Screw dislocation: Formed by the shear stress that is applied to produce the distortion.

Surface defects

(Two-Dimensional)

Grain boundary defect: Due to the orientation mismatch at the grain boundary the bond length is more and can be easily broken.

Tilt boundary defect: When the orientation mismatch at the grain boundary is 0.5° - 1° then grain boundaries are called tilt boundaries.