Frenkel pairs are used to denote the combination of vacancies and self-interstitials. For undoped crystals to maintain charge neutrality, it is necessary for the quantities of vacancies and self-interstitials to be balanced and equal. The occurrence of Frenkel disorder can be observed within the silver sublattices of both silver chloride and silver bromide. Schottky disorder occurs when an equal number of vacancies are formed in both sublattices. In an undoped crystal, maintaining charge neutrality necessitates having equivalent concentrations of cation and anion vacancies. In the majority of alkali halides and numerous oxides, it has been observed that Schottky disorder is the primary factor influencing the distribution of defects.