Question

Difference between Schottky and Frenkel defects

Answer 1

Schottky v/s Frenkel

Schottky Defect
1. Equal number of cations and anions are missing from the lattice sites.

2. Found in highly ionic compounds with high coordination numbers and where the cations and anions are of similar size.

3. Density of the solid decreases


FrenkelFrenkel Defect
1. A cation leaves the normal lattice site and occupies an interstitial site.

2. Found in ionic compounds with low coordination numbers and where the anions are much larger in size than cations.

3. Density of the solid remains the same.

* coordination number: It is defined as the number of nearest neighbours of a particle in a closed packed structure.