Dear Hongsheng!<div> The flag is "calculation" = 'scf' for single point energy calculation. But I will suggest you if you want to test the convergence for structure then you must relax the atomic position as well as cell volume, because the single point energy calculation will not relax the stress and forces. So for bulk structures "calculation = 'vc-relax' is the way to test the convergence with respect to energy, because that will release the stress and forces in the system. I hope it helps. Feel free to ask any doubt further.<br>
<br><div class="gmail_quote">On Wed, May 25, 2011 at 10:19 PM, Hongsheng Zhao <span dir="ltr"><<a href="mailto:zhaohscas@yahoo.com.cn">zhaohscas@yahoo.com.cn</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
Hi all,<br>
<br>
I've learned that the single point energy calculation should be the<br>
most appropriate method for any type of convergence testings (whether<br>
that be k-point, cutoff, fine grid or cell size). I want to know if<br>
there are keywords/flags within PWSCF for single point energy calculation?<br>
<br>
Regards.<br>
<font color="#888888">--<br>
Hongsheng Zhao <<a href="mailto:zhaohscas@yahoo.com.cn">zhaohscas@yahoo.com.cn</a>><br>
School of Physics and Electrical Information Science,<br>
Ningxia University, Yinchuan 750021, China<br>
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</font></blockquote></div><br><br clear="all"><br>-- <br>Regards,<br>MOHNISH,<br>-----------------------------------------------------------------<br>Mohnish Pandey<br>Y6927262,5th Year dual degree student,<br>Department of Chemical Engineering,<br>
IIT KANPUR, UP, INDIA<br>-----------------------------------------------------------------<br>
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