Write a note on Frenkel defect.

Explanation

Interstitial defect of Frenkel defect :
(1) In this, an ion in the
ionic solid leaves a regular
lattic site and occupies a
lattice points or interstitial
points. This defect is called
Frenkel or interstitial defect.
(2) Frenkel defect arises in case of ionic solids with
relatively smaller cationic
size which can fit into interstitial space and difference in ionic radii is
large. This defect is also called dislocation defect.
(3) This defect is observed in AgCl solid by `Ag^(+)` ions, in ZnS solid by `Zn^(2+)` ions, etc.
(4) Frenkel defect does not alter the density of the crystalline solid.