The energy gaps (E_g) between valence band and conduction band for diamond, silicon and germanium are in the order

$\begin{array}{r}{\mathrm{E}}_{\mathrm{g}}\left(\text{ diamond }\right)>{\mathrm{E}}_{\mathrm{g}}\left(\text{ silicon }\right)>{\mathrm{E}}_{\mathrm{g}}\left(\text{ germanium }\right)\\ \end{array}$

$\begin{array}{r}{\mathrm{E}}_{\mathrm{g}}\left(\text{ diamond }\right)<{\mathrm{E}}_{\mathrm{g}}\left(\text{ silicon }\right)<{\mathrm{E}}_{\mathrm{g}} (\mathrm{germanium})\\ \end{array}$

$\begin{array}{r}{\mathrm{E}}_{\mathrm{g}}\left(\text{ diamond }\right)={\mathrm{E}}_{\mathrm{g}}\left(\text{ silicon }\right)={\mathrm{E}}_{\mathrm{g}}\left(\text{ germanium }\right)\\ \end{array}$

$\begin{array}{r}\left.{\mathrm{E}}_{\mathrm{g}}\left(\text{ diamond }\right)>{\mathrm{E}}_{\mathrm{g}}\left(\text{ germanium }\right)\right)>{\mathrm{E}}_{\mathrm{g}}\left(\text{ silicon }\right)\\ \end{array}$