<div class="gmail_quote"><br>Hi everybody.  <br><div class="gmail_quote"><div class="im"><div><div>      Sorry to post this email again cause the image in this one is bigger and easy to see.<br>      I tried to plot the bandstructure for carbon nanotube(5,5), however, the result looks strange. I have 20 carbon atoms in a unitcell, and I set the number of bands(nbnd=80 or 48).<br>

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    nbnd=80 is out of the consideration that conduction bands+valence bands.</div><a href="http://imageshack.us/photo/my-images/51/cnt55bands80.jpg/" target="_blank"></a><div class="im"><br><a href="http://imageshack.us/photo/my-images/36/cnt55bands80.jpg/">http://imageshack.us/photo/my-images/36/cnt55bands80.jpg/</a><br>

    nbnd=48 is from the 20% more for metal.(here the carbon nanotube is metallic)<br></div><a href="http://imageshack.us/photo/my-images/202/cnt55bands48.jpg/" target="_blank"><br></a><div class="im"><a href="http://imageshack.us/photo/my-images/163/cnt55bands48.jpg/">http://imageshack.us/photo/my-images/163/cnt55bands48.jpg/</a><br>

<br>    The third picture is after I added no_overlap=.true. in the <a href="http://bands.in" target="_blank">bands.in</a> file for nbnd =48.<br><a href="http://imageshack.us/photo/my-images/850/cnt55bands48nooverlap.jpg/">http://imageshack.us/photo/my-images/850/cnt55bands48nooverlap.jpg/</a><br>
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    All the three pictures are far from the band structure in literature, and I don't know if they are wrong. <br>
    Can somebody give me an advice and I apprieciate it very much. <br>    Thank you!<br>   <br>    Best regards.<br></div></div></div><div class="im"><font color="#888888"><font color="#888888"><br>Chengyu Yang<br>MMAE<br>
University of Central Florida, USA<br>

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