  <b>small_basis</b>  </span>  
<b><font color="red">EXPERIMENTAL</font> </b> 
<br><br>
<i>Optional</i><br>
Default: none<br><br>
Calls for a smaller basis set used to represent the virtual orbital space with fewer functions. Only meaningful for GW.</li><br>
<hr>
<a name=step_sigma><li>                 <span style="display:inline-block;background:#EEEEEE;width:400px">               <b>step_sigma</b>  </span>  
<br><br>
<i>Optional</i><br>
Default: 0.01<br><br>
Sets the spacing between frequencies in the fin