<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;"><DIV>Dear Hai-Ping</DIV>
<DIV>Nick is right, DCC for partial periodicity is not in the cvs version of the code yet. </DIV>
<DIV>The main issue is not the "whichbc" parameter that you've checked in the Multigrid directory. The way that the true potential is calculated (add_boundary.f90) and Poisson equation that is solved should be modified accordingly (add_dcc_field.f90).</DIV>
<DIV>Regards, </DIV>
<DIV> </DIV>
<DIV>Emine Kucukbenli, </DIV>
<DIV>grad student, SISSA, Italy.<BR><BR>--- On <B>Thu, 2/19/09, lan haiping <I><lanhaiping@gmail.com></I></B> wrote:<BR></DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: rgb(16,16,255) 2px solid">From: lan haiping <lanhaiping@gmail.com><BR>Subject: Re: [Pw_forum] DCC correction to electrostatic potential<BR>To: "PWSCF Forum" <pw_forum@pwscf.org><BR>Date: Thursday, February 19, 2009, 4:12 AM<BR><BR>
<DIV id=yiv1965998638>Dear Nick, <BR>Thanks. <BR>Therefore, My problem is just due to wrong BC handling by QE. I found the settings for boundary conditions at $QE/Multigrid, and just thought it should be OK for all possible aperiodic situations.<BR>Would you mind to tell me <BR>which subroutine in $QE/EE accounts for boundary settings ?<BR><BR>Regards,<BR>Hai-Ping<BR><BR>
<DIV class=gmail_quote>On Thu, Feb 19, 2009 at 1:20 AM, Nicholas E. Singh-Miller <SPAN dir=ltr><<A href="mailto:nedward@mit.edu" target=_blank rel=nofollow>nedward@mit.edu</A>></SPAN> wrote:<BR>
<BLOCKQUOTE class=gmail_quote style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Dear Hai-Ping,<BR><BR>I am looking at espresso-4.1CVS.<BR><BR>Looking at the subroutines in EE/, it looks like the DCC correction is<BR>currently only coded for isolated systems -- in which case the<BR>calculataion of BCs for a CNT would cut through the charge density. (but I<BR>could be missing something).<BR><BR>Regads,<BR><BR>Nick<BR>
<DIV class=Ih2E3d><BR>On Wed, 18 Feb 2009, lan haiping wrote:<BR><BR>> Dear All,<BR>><BR>> I did test calculations on DCC correction implemented in CVS version.<BR>> I came to problems when i examine the results of electrostatic potential.<BR>> Would you please give me some hints ?<BR>> My test calculation is a CNT (10,10) system, and the setting for<BR>> DCC correction is<BR>> which_compensation ='dcc',<BR>> ecutcoarse = 100.0,<BR>> n_charge_compensation= 5,<BR>> nlev = 4,<BR>> whichbc(1)= 0, whichbc(2)=0,<BR>> whichbc(3)=1,<BR>> But the final fermi energy i obtained is -3.99 eV, which is not consistent<BR>> with<BR>> previous report on workfunction of CNTs(about 4.6 eV ).<BR>><BR>> Best,<BR>>
Hai-Ping<BR>><BR>><BR>><BR><BR></DIV>*****************************************<BR>Nicholas E. Singh-Miller<BR>Ph.D. Candidate<BR>Prof. Marzari Group (<A href="http://quasiamore.mit.edu/" target=_blank rel=nofollow>quasiamore.mit.edu</A>)<BR>Materials Science and Engineering<BR>Massachusetts Institute of Technology<BR>13-4066<BR>(617)324-0372<BR>*****************************************<BR>_______________________________________________<BR>Pw_forum mailing list<BR><A href="mailto:Pw_forum@pwscf.org" target=_blank rel=nofollow>Pw_forum@pwscf.org</A><BR><A href="http://www.democritos.it/mailman/listinfo/pw_forum" target=_blank rel=nofollow>http://www.democritos.it/mailman/listinfo/pw_forum</A><BR></BLOCKQUOTE></DIV><BR><BR clear=all><BR>-- <BR>Hai-Ping Lan <BR>Department of Electronics ,<BR>Peking University , Bejing, 100871<BR><A href="mailto:lanhaiping@gmail.com" target=_blank rel=nofollow>lanhaiping@gmail.com</A>, <A
href="mailto:hplan@pku.edu.cn" target=_blank rel=nofollow>hplan@pku.edu.cn</A><BR></DIV><PRE>_______________________________________________
Pw_forum mailing list
Pw_forum@pwscf.org
http://www.democritos.it/mailman/listinfo/pw_forum
</PRE></BLOCKQUOTE></td></tr></table><br>