The atomic diameter of a BCC crystal (if a is lattice parameter) is _____?

a/(4/√3)

a/4/13)

al(4/12)

None of these

In a Body-Centered Cubic (BCC) lattice, the relation between the lattice parameter a and atomic radius r is: $4 r = \sqrt{3} a$

Since atomic diameter = 2r, solving gives: $Atomic Diameter = \frac{4 r}{2} = \frac{a}{4 / \sqrt{3}}$