Question

Right option of the number of tetrahedral and octahedral voids in hexagonal primitive unit cell are:

• A. $2,1$
• B. $6,12$
• C. $8,4$
• D. $12,6$

Answer 1

The correct option is D $12,6$

For hexagonal primitive unit cell,

$\text{Number of effective atoms per unit cell,}Z=6$

$\therefore \text{Total no. of tetrahedral voids}=2Z$

$=2\times 6$

$=12$

and, Total no. of octahedral voids $=Z$

$=6$

Hence, option (c) is correct.