Question
How would you account for the following:
Frenkel defects are not found in alkali metal halides.
Solution
The frenkel defect is favoured by a large diffrance in size between the positive and negtive ion the metal cation are generally smaller than the anion which occupy the vacant lattice site or hole.
Frenkel defects are not found in alkali metal halides because the ions cannot get into interstitial positions due to their large sizes.
