<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Dear Loc Duong Dinh,<div><br></div><div> have you haver heard about "refolding" of the band structure (in the context of supercells)? If not, first have a look at some good electronic structure textbook. </div><div>The band structure is actually the same, but in practice you are visualizing it in a different way. Try to compute the (fully converged) DOS for the two different unit cells and compare them (with appropriate weights). What do you see?</div><div><br></div><div><br></div><div>GS</div><div><br><div><div>Il giorno 22/lug/2010, alle ore 05.16, loc duong ding ha scritto:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Dear all,<br><br>I have a problem when I calculate band structure of graphene. The band structure <br>of graphene calculated by unit of 2 atoms and 8 atoms is different. the gap at <br>gama point as well as M point are totally different. <br><br><br>In general case, unit of 2 atoms and unit of 8 atoms both create graphene <br>strucutre. I can not unserstand why they are different? Is my understanding is <br>wrong? <br><br><br>I know this is the general question but I hope I can receive helpful <br>instructions. <br><br><br>I aprreciate all ypur helps. <br> <br>Sincerely,-----------------------------------------------<br>Loc Duong Dinh<br>Ms-Ph.D Student<br>Sungkyunkwan Advanced Institute of Nanotechnology,<br>Sungkyunkwan University,<br>Suwon, 440-746, Korea <br>Email: <a href="mailto:mambom1902@yahoo.com">mambom1902@yahoo.com</a>, <a href="mailto:ddloc@skku.edu">ddloc@skku.edu</a> <br><br><br><br>_______________________________________________<br>Pw_forum mailing list<br><a href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br>http://www.democritos.it/mailman/listinfo/pw_forum<br></div></blockquote></div><br><div>
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div><span class="Apple-style-span" style="color: rgb(126, 126, 126); font-size: 16px; font-style: italic; "><br class="Apple-interchange-newline">§ Gabriele Sclauzero, EPFL SB ITP CSEA</span></div><div><font class="Apple-style-span" color="#7E7E7E"><i> PH H2 462, Station 3, CH-1015 Lausanne</i></font></div></span>
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