Question

the number of carbon atoms per unit cell of diamond unit cell is 8 ,verify how it get​

Answer 1

Answer:

In diamond, every C is tetrahedrally bonded to 4 other C atoms. It unit cell is cubic where C atoms are located at the corners , face centres and occupying the alternate tetrahedral voids:

Contribution form corners=8×1/8=1

Contribution from face centres =6×1/2=3

Contribution form tetrahedral voids=8×1/2=4

Thus, total C atoms per unit of diamond is 4. Note that total number of tetrahedral voids is 8 and only half of them are captured.