Optional</i><br>
Default: yes<br><br>
Build the X2C approximate Hamiltonian (H**new) to reproduce state energies. with  H = S C e C**-1, H**dagger S C e C**-1, and H**new = 1/2 ( H + H**dagger). Default yes.</li><br>
<hr>
<a name=check_CdSC_x2c><li>                 <span style="display:inline-block;background:#EEEEEE;width:400px">               <b>check_CdSC_x2c</b>  </span>  
<b><font color="red">EXPERIMENTAL</font> </b> 
<br><br>
<i>Optional</i><br>
Default: yes<br><br>
Check whether C**dagger S C = I. It