Schottky defect

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About Schottky defect:

 This defect arises in the ionic and was discovered by German scientist Shottky in 1930. This defect arises when equal number of +ve and -ve ions are found missing from their normal lattice sites. Taking example of an ideal crystal A+B- the arrangement of ions in an ideal crystal and Schottky defect crystal are shown below


 
An ideal crystal

Schottky defect in crystal


In case of (I) Strongly ionic compounds having high co-ordination number and (ii) Cation the anions having almost equal sizes.


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