Discussion Forum



1)

The number of tetrahedral and octahedral voids in CCP unit cell are respectively


A) 4,8

B) 8,4

C) 12,6

D) 6,12

Answer:

Option B

Explanation:

In a closed packet structure (CCP or HCP) if there are n spheres (atoms or ions) in packing then,

 Number of octahedral voids=n

 Number of tetrahedral voids=2n

In CCP;

Number of atoms=4

So, number of octahedral voids=4

Number of tetrahedral voids=8