Question

Homework
What is packing efficiency?
Explain packing efficiency of simple cubic unit cell and bcc unit cell?
What is packing fraction?
Explain FCC unit cell?​

Answer 1

Answer:Packing efficiency is the ratio of volume of the atoms present per unit cell by the volume the unit cell multiplied by 100. It can be said to be the space occupied by atoms in an unit cell.

In simple cubic unit cell packing efficiency = 52%( a =2r in SC . (4/3*pi * r^3)  / 8 r^3) *100 = 52.4%.

In bcc , packing efficiency = 68%.

Packing fraction is volume of atoms present per unit cell by volume of unit cell.

In FCC atoms are present in all corners and face centres. There are totally 4 atoms in the unit cell.

Explanation: