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<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 150%"><SPAN style="mso-bidi-language: FA">Dear Paolo</SPAN></P>
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<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 150%"><SPAN style="mso-bidi-language: FA">Thanks very much for your reply. I read the lectures and I understand that offset shift only points and not change the total energy. Am I wrong? <o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 150%">I calculated energy for a system with <SPAN class=yshortcuts>two kinds</SPAN> of k_points (2 2 5 0 0 0 and 2 2 5 1 1 1) and I observed different energy for each of them. How to determine the offset for any kpoints? Is there need for convergence?</P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 150%">Thanks in advance<BR><BR>Mahkameh Vaziri<BR> <I><SPAN style="FONT-SIZE: 10pt; LINE-HEIGHT: 150%">PhD student of <SPAN class=yshortcuts>physical chemistry</SPAN><BR>K. N. Toosi university of Technology, Tehran, Iran</SPAN></I><SPAN style="mso-bidi-language: FA"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 150%"><SPAN style="mso-bidi-language: FA"><o:p> </o:p></SPAN></P></DIV></div><br>
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