It sounds like you got some problems with smearing. I would try other smearing methods.<br clear="all">--------------------------------------------------<br>Duy Le<br>PhD Student<br>Department of Physics<br>University of Central Florida.<br>

<br>"Men don't need hand to do things"<br>
<br><br><div class="gmail_quote">On Mon, May 24, 2010 at 2:33 PM, shu xu <span dir="ltr"><<a href="mailto:sxu2@ncsu.edu">sxu2@ncsu.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">

<div class="gmail_quote"><blockquote class="gmail_quote" style="border-left:1px solid rgb(204, 204, 204);margin:0pt 0pt 0pt 0.8ex;padding-left:1ex">hi, I am doing relaxation of graphene on SiC with tpss pseudopotential and received the following error message.<br>


I did the relaxation with GGA pseudopotentials and there was no problem. Why it could not get through with tpss PP?<br>
<br><br><br>  iteration #  8     ecut=    40.00 Ry     beta=0.30<br>     Davidson diagonalization with overlap<br>     ethr =  1.00E-02,  avg # of iterations =  1.0<br><br> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br>




     from efermig : error #         1<br>
            <br>
          <br>
     internal error, cannot braket Ef<br>
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br><br>part of the input file is :<br><br><br><br>                  <br>                   forc_conv_thr = 1.0D-3,<br>                    etot_conv_thr = 1.0D-4,<br>



                     tstress = .true. ,<br>                     tprnfor = .true. ,<br>                       dipfield = .true. ,<br>                       tefield = .true. ,<br> /<br> &SYSTEM<br>                      <br>



                     ecutwfc = 40 ,<br>                     ecutrho = 320 ,<br>                 occupations = 'smearing' ,<br>                     degauss = 0.01D0 ,<br>                    smearing = 'mp' ,<br>



                         edir = 3,<br>                         eamp = 0,<br>                         eopreg = 0.01,<br>                        emaxpos = 0.6302,<br> /<br> &ELECTRONS<br>                 mixing_mode = 'plain' ,<br>



                 mixing_beta = 0.3 ,<br>             diagonalization = 'david' ,<br>              <br> /<br>&IONS<br>           pot_extrapolation = 'first_order',<br>           wfc_extrapolation = 'first_order' <br>



<br>
</blockquote></div><br>
<br>_______________________________________________<br>
Pw_forum mailing list<br>
<a href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br>
<a href="http://www.democritos.it/mailman/listinfo/pw_forum" target="_blank">http://www.democritos.it/mailman/listinfo/pw_forum</a><br>
<br></blockquote></div><br>