<DIV>Dear Stefaan and Torsten:</DIV>
<DIV>thanks for your kind help.</DIV>
<DIV><B><I>Torsten Andersen <thor@physik.uni-kl.de></I></B> wrote:</DIV>
<BLOCKQUOTE class=replbq style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">And if you are looking for anything like a dipole moment, you will have <BR>to break the inversion symmetry (which is broken at an interface, but <BR>restored with symmetric slabs)...<BR><BR>Best regards,<BR>Torsten Andersen.<BR><BR>Stefaan Cottenier wrote:<BR>>> In order to simulate the interface between two bulk-like slabs, we<BR>> <BR>> must ensure the presence of a bulk-like slab. So I want to know is there a<BR>> criterion for the presence of a bulk-like slab?<BR>> <BR>> It depends on the property you are looking at. For very local properties (a<BR>> hyperfine field, for instance), 5 to 7 layers are enough. More extended<BR>> properties (a strain field near an interface) you need more. In my<BR>> experience, you should use at least 7 layers (for 5 layers usually there are<BR>> clear signs of communication between the two surfaces/interfac!
es of
the<BR>> slab). A possible strategy: calculate the property you are interested in in<BR>> a test system with 5,7,9,... layers, and see where it saturates.<BR>> <BR>> Stefaan<BR>> <BR>> _______________________________________________<BR>> Wien mailing list<BR>> Wien@zeus.theochem.tuwien.ac.at<BR>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien<BR>> <BR><BR>-- <BR>Dr. Torsten Andersen TA-web: http://deep.at/myspace/<BR>AG H黚ner, Department of Physics, Kaiserslautern University, and<BR>Condensed Matter Theory Group, Department of Physics, Uppsala University<BR>Web: http://www.fysik4.fysik.uu.se/ http://www.physik.uni-kl.de/ <BR><BR><BR>_______________________________________________<BR>Wien mailing list<BR>Wien@zeus.theochem.tuwien.ac.at<BR>http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien</BLOCKQUOTE><p><br><hr size=1><b>Do You Yahoo!?</b><br>
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