Result of Frenkel defect

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Results of Frenkel defect: 

 1- It increase the electrical conductivity of the crystal because of the presence of vacancy in crystal lattice. 

2- It decrease the stability or lattice energy of the crystal.

3- This defect does not change the density of crystal because the number of ions per unit volume remain same in the crystal.

4- It increase the dielectric constant of the crystalline solid as the similarly changed ions come closer.
This defects are generally found in (i) AgCl,AgBr,Agl etc.
It is because Ag+ ion being small in size occupy the interstitial sites leaving its own position in crystal lattice (ii) Further this defect is also noticed in ZnS crystal because of small size of Zn²+ ion which can fit in its own interstitial sites. (iii) Alkali metal halides don't exhibit this defect because of large size of alkali metal ions.

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