Cations are present in the interstitial sites in __________.
(i) Frenkel defect
(ii) Schottky defect
(iii) Vacancy defect
(iv) Metal deficiency defect
The answer is the option (i) Frenkel defect
Frenkel effect is when a cation is missing from the normal lattice position and is occupying interstitial site. It generally occurs in Ionic solids where the anion is larger than the cation.