(Solved): solid state physics complete the solution There should be 12 terms at the end. Find them ...

solid state physics

 complete the solution

There should be 12 terms at the end. Find them

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EX Fro \[ \begin{array}{l} \left(E x \text { fic } R_{i}\right.=(\pm 1, \pm 1,0) \frac{a}{2} \\ ,(\pm 1,0, \pm 1) \frac{a}{2} \\ (0, \pm 1, \pm 1) \frac{a}{2} \\ 12 \text { nearesf nejgh bor } \end{array} \] \[ \begin{array}{l} \vec{K}=k_{x} \cdot+k_{y} \int+k_{z} \hat{k} \\ E_{k}=E_{s}+\sum_{j=1}^{12} e^{i \overrightarrow{k_{1} \cdot R_{1}} \gamma} \gamma \\ =E_{s}+\gamma\left[e^{i k_{x} \frac{9}{2}} e^{i k_{y} \frac{a}{2}}\right]+ \end{array} \]