Chapter 15, Problem 15.6P

Interpretation Introduction

Interpretation:

The structure of lithium is whether fcc or bcc has to be determined.

Concept Introduction:

The separation of planes can be calculated for a cubic crystal system using miller indices as,

    $\begin{array}{c}\frac{\text{1}}{{\text{d}}^{\text{2}}}\text{=}\frac{{\text{h}}^{\text{2}}\text{+}{\text{k}}^{\text{2}}{\text{+l}}^{\text{2}}}{{\text{a}}^{\text{2}}}{e}^{i\theta }\\ \\ \text{d}\text{=}\frac{\text{a}}{\sqrt{{\text{h}}^{\text{2}}\text{+}{\text{k}}^{\text{2}}{\text{+l}}^{\text{2}}}}.\end{array}$

Where,

h, l, and k are miller indices which indicates each plane.

d is distance of separation of plane and a is the side of the plane.

The density is expressed by the formula,

  $\text{d}=\frac{\text{Z}\times \text{M}}{{\text{a}}^3\times {\text{N}}_{\text{a}}}$

Where d is the density, $Na$ is the Avogadro number, M is the mass and a is the edge length.