<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>Il giorno 11/mar/2011, alle ore 19.37, pari shok ha scritto:</div><br class="Apple-interchange-newline"><blockquote type="cite">Hello,<br>I have a question and I appreciate your help in advance.<br>I am making a supercell by repeating a unit cell of SiC. Then, instead of 8 atom in a hexagonal structure, there are 72 atoms in a supercell.<br>My question is about the number of bands. <br>
Theoretically, the number of bands would be just the same for the unit cell (32 in this case) </blockquote><div><br></div><div>Why 32? Since you have 8 atoms per cell, either Si or C, the number of electrons should be 4*8=32, so nbnd=16 should be sufficient (for collinear calculations).</div><div><br></div><br><blockquote type="cite">and even if you increase them in the input file, they should just have degeneracy and overlap. However, they are not.<br>I was wondering how I can interpret the bands.<br></blockquote><div><br></div><div>For this point, please refer to Duy Le's reply and perform a search about "band refolding" on the forum (or in any electronic structure book).</div><div><br></div><div><br></div><div>HTH</div><div><br></div><div>GS</div><div><br></div><blockquote type="cite">
Yours<br>P Shok<br>UMD <br>
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<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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