Any deviation from the perfectly ordered arrangement constitutes a defect or imperfection. The compounds in which the number of irregularity are present in the arrangement of atoms or ions are called atomic imperfections or point defects. These may be stochiometric or non - stoichlometric. Stoichiometric defects are further classified into Schottky defects in which number of positive and negative ions are missing in equal ratio and Frenkel defects in which an ion leaves its correct lattice sites and occupies on interstitial site. Schottky defect is more common in ionic compounds with high co-ordination number and where the size of positive and negative ions are almost equal, while in Frenkel defects are common in ionic compounds, which have low co-ordination number and in which there is large difference in size between positive and negative ions.
When an ion leaves ir correct lattice and occupies interstital sites in its crystal lattice, it is called

Options

A. Frenkel defect
B. Schottky defect
C. impurity defect
D. vacancy defect

Answer

A