Explain the following term with suitable examples: F-centres. - Vidyadip

Question

Explain the following term with suitable examples:
F-centres.

✓

Answer

F-centres:F-centres – This is type of defect and called metal excess defect. These type of defects seen because of missing of anions from regular site leaving a hole which is occupied by electron to maintain the neutrality of the compound. Hole occupied by electron is called F-centre and responsible for showing colour by the compound. example sodium chloride impart yellow colour beacuse of F centre.

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