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<P class=MsoNormal style="MARGIN: 0pt"><SPAN lang=EN-US
style="mso-ansi-language: EN-US"><FONT size=3><FONT
face="Times New Roman">Hi<SPAN style="mso-spacerun: yes">
</SPAN><?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office"
/><o:p></o:p></FONT></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0pt"><SPAN lang=EN-US
style="mso-ansi-language: EN-US"><FONT size=3><FONT face="Times New Roman"><SPAN
style="mso-spacerun: yes"> </SPAN>I'm performing calculations
for defective supercells.<SPAN style="mso-spacerun: yes">
</SPAN><o:p></o:p></FONT></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0pt"><SPAN lang=EN-US
style="mso-ansi-language: EN-US"><FONT size=3><FONT face="Times New Roman">The
formation energy for a system could be=<SPAN
style="mso-spacerun: yes">
</SPAN><o:p></o:p></FONT></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0pt"><SPAN lang=EN-US
style="mso-ansi-language: EN-US"><FONT size=3><FONT
face="Times New Roman">E(defect_formation)=E(defective)-[E(bulk)+E(isolated_atom)].<SPAN
style="mso-spacerun: yes">
</SPAN><o:p></o:p></FONT></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0pt"><SPAN lang=EN-US
style="mso-ansi-language: EN-US"><FONT size=3><FONT face="Times New Roman"><SPAN
style="mso-spacerun: yes"> </SPAN>My problem is related with
the total energy for an isolated atom, Wien take as a reference the average
potential of the supercell, but how to deal with it in the case of a single
atom. So, how can I perform a calculation for an isolated atom in order to be
considered in the previous formula?<SPAN style="mso-spacerun: yes">
</SPAN><o:p></o:p></FONT></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0pt"><SPAN lang=EN-US
style="mso-ansi-language: EN-US"><FONT size=3><FONT face="Times New Roman"><SPAN
style="mso-spacerun: yes"> </SPAN>Thanks in advance<SPAN
style="mso-spacerun: yes"> </SPAN><o:p></o:p></FONT></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0pt"><SPAN lang=EN-US
style="mso-ansi-language: EN-US"><FONT size=3><FONT
face="Times New Roman">Ricardo<o:p></o:p></FONT></FONT></SPAN></P></FONT></DIV>
<DIV><FONT face=Arial
size=2>-------------------------------------------------------------------------<BR>-----
Ing. Quím. Ricardo Faccio<BR> <BR> Mail: Cryssmat-Lab., Cátedra de
Física, DETEMA<BR> Facultad de Química, Universidad de la
República<BR> Av. Gral. Flores 2124, C.C.
1157<BR> C.P. 11800, Montevideo,
Uruguay.<BR> E-mail: <A
href="mailto:rfaccio@fq.edu.uy">rfaccio@fq.edu.uy</A><BR> Phone: 598 2
9241860 Int.
109<BR>
598 2 9290705<BR> Fax: 598 2 9241906<BR>
Web: <A
href="http://cryssmat.fq.edu.uy/ricardo/ricardo.htm">http://cryssmat.fq.edu.uy/ricardo/ricardo.htm</A></FONT></DIV></BODY></HTML>