Question

Gold crystallizes in fcc unit cell.What is the lenghth of the side of the cell?

Answer 1

we know that,

the atom radius of gold R = 0.144 nm.

As gold crystallizes in face-centered unit cell, then the length of its edge will be given as,

edge a = 2√2 R

now

putting R = 0.144 nm,

a= 2√2 × 0.144

a = 0.407 nm

hence the length of the side of the cell is .407 nm