Answer:
56°
Explanation:
First calculate [tex]a:[/tex]
[tex]a=2 R \sqrt{2}=2(0.1246) \sqrt{2}=0.352 \mathrm{nm}[/tex]
The interplanar spacing can be calculated from:
[tex]d_{111}=\frac{a}{\sqrt{1^{2}+1^{2}+1^{2}}}=\frac{0.352}{\sqrt{3}}=0.203 \mathrm{nm}[/tex]
The diffraction angle is determined from:
[tex]\sin \theta=\frac{n \lambda}{2 d_{111}}=\frac{1(0.1927)}{2(0.2035)}=0.476[/tex]
Solve for [tex]\theta[/tex]
[tex]\theta=\sin ^{-1}(0.476)=28^{\circ}[/tex]
The diffraction angle is:
[tex]2 \theta=2\left(28^{\circ}\right)=56^{\circ}[/tex]
