Calculate the efficiency of packing in case of a metal crystal for
face-centred cubic (with the assumptions that atoms are touching each other).

Question

Calculate the efficiency of packing in case of a metal crystal for face-centred cubic (with the assumptions that atoms are touching each other).

Philoid · Accepted Answer

Let the base of the hexagon is a and the height is c

Each angle in hexagonal will be 60 degree at the base

Packing efficiency of Hexagonal close- packed lattice

a = 2r c = 1.633a

= 74%

Calculate the efficiency of packing in case of a metal crystal forface-centred cubic (with the assumptions that atoms are touching each other).