Question

Explain the following terms with suitable examples :
(i) Schottky defect
(ii) Frenkel defect.
(iii) Interstitial defect
(iv) F-centers

Answer 1

Schottky defects :-

This type of defect is created when on positive ion and on negative ion are missing from their respective position having behind a pair of words.

• This defect is also called vacancy defect in ionic solid.
• example of schottky defect sodium chloride, potassium chloride and caesium chloride etc

Frenkel Defect :-

This type of defect is created when an iron leaves its correct later side and occupies an interstitial site.

• it is a combination of vacancy defect and interstitial defect.
• example of Frankel defect age zinc sulphide, silver, chloride silver bromide and Agi etc.

Interstitial defect:-

This type of defect is caused due to the presence of constituent particle in the normally back and interstitial site in the crystal.

• the constituent particle occupying the interestitial sides are called interstitials.
• Example Nacl,KCl etc

F - Centre :-

the holes occupied by electron called centre and are responsible for the colour of the compound .