Chemistry - Solid State Question with Solution | TestHub

Iron crystallizes in the two body centered Cubic Lattice the $\alpha$-form below $750^{\circ }\mathrm{C}$ and $\gamma -$ form above $1400^{\circ }\mathrm{C}$ and in a face centered cubic $\beta$ - form between those two temperatures. If the maximum ratio of foreign paraticle occupying a hole in the face of a body centered cubic unit cell to the host iron radius is $\frac{4\sqrt{a}-a}{a}$, then value of ' $a$ ' is $\_\_\_\_$