Question

The distance between the two nearest octahedral voids in fcc lattice would be :

• A. $\sqrt{3}a$
• B. $\frac{\sqrt{3}a}{2}$
• C. $\frac{\sqrt{3}a}{3}$
• D. $\frac{a}{\sqrt{2}}$

Answer 1

The correct option is D $\frac{a}{\sqrt{2}}$

The distance between two nearest octahedral voids in fcc lattice is the distance between an edge-centre and the body-centre which is
$\sqrt{(\frac{a}{2}{)}^2\times (\frac{a}{2}{)}^2}=\frac{a}{\sqrt{2}}$