Did you read what I said? Got it. By the way, I've just realized that I did not thank Mehmet and Hui Wang.
On 03/09/2011 08:57 PM, Duy Le wrote: > On Thu, Mar 10, 2011 at 9:52 AM, Eric Germaneau<germaneau at gucas.ac.cn> > wrote: >> Dear Mehmet and Hui Wang, >> >> That's what I did. >> From my calculations the occupied and unoccupied bands touch only at K >> point. >> I was just confused because the scf calculation does not output a zero gap. >> I mean the line "highest occupied, lowest unoccupied level" shows two >> different values and I expected them to be equal. > This was just explained by Mehmet. Check it again >> So, it seems I did not too bad in fact. >> But how to experimentally get a zero gap then? >> Thanks, >> >> Eric. >> > -------------------------------------------------- > Duy Le > PhD Student > Department of Physics > University of Central Florida. > > "Men don't need hand to do things" >> On 03/09/2011 07:02 AM, Mehmet Topsakal wrote: >> >> Dear Eric, >> In addition, if you select 18x18x1 kpoints, your mesh should include both K >> and M points. >> But for a band-structure calculation, you should arrange a kpoints list >> along special directions, such as from GAMMA-to-M-to-K-to-GAMMA, and do a >> nscf calculation.... >> >> >> On Wed, Mar 9, 2011 at 11:28 AM, xirainbow<nkxirainbow at gmail.com> wrote: >>> Dear Eric: >>> The occupied and unoccupied bands touch each other only at M point(or K >>> point, I forget it). >>> You must include this point in you k-mesh. >>> Furthermore, if you include spin-orbital coupling, the band gap will be >>> opened at this point. >>> >>> On Thu, Mar 10, 2011 at 1:30 AM, Eric Germaneau<germaneau at gucas.ac.cn> >>> wrote: >>>> Dear all, >>>> >>>> I'm trying to compute graphene's band gap but get stuck. >>>> From my understanding a scf calculation should provide the same energy >>>> for the highest occupied and lowest occupied level which means a zero gap. >>>> I played with the number a kpoints a finally got a band gap of 0.57 which >>>> is not null. >>>> The scf convergence looks good. >>>> I'm not (yet) an expert in DFT calculation so may did something wrong or >>>> misunderstood something here. >>>> So, I wonder if someone has already successfully performed such >>>> calculation. >>>> I have attached my input file. >>>> Thanks in advance, >>>> >>>> Eric. >>>> >>>> -- >>>> Be the change you wish to see in the world >>>> ? Mahatma Gandhi ? >>>> >>>> Dr. ?ric Germaneau >>>> >>>> College of Physical Sciences >>>> Graduate University of Chinese Academy of Sciences >>>> Yuquan Road 19A >>>> Beijing 100049 >>>> China >>>> >>>> Please consider the environment before printing this email. >>>> Consid?rez svp l'environnement avant d'imprimer cet email. >>>> _______________________________________________ >>>> Pw_forum mailing list >>>> Pw_forum at pwscf.org >>>> http://www.democritos.it/mailman/listinfo/pw_forum >>>> >>> >>> >>> -- >>> ____________________________________ >>> Hui Wang >>> School of physics, Fudan University, Shanghai, China >>> >>> _______________________________________________ >>> Pw_forum mailing list >>> Pw_forum at pwscf.org >>> http://www.democritos.it/mailman/listinfo/pw_forum >>> >> >> >> -- >> >> Mehmet Topsakal (Ph.D. Student) >> UNAM-Institute of Materials Science and Nanotechnology. >> Bilkent University. 06800 Bilkent, Ankara/Turkey >> Tel: 0090 312 290 3527 ; Fax: 0090 312 266 4365 >> http://www.researcherid.com/rid/A-5015-2010 >> >> >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum at pwscf.org >> http://www.democritos.it/mailman/listinfo/pw_forum >> >> -- >> Be the change you wish to see in the world >> ? Mahatma Gandhi ? >> >> Dr. ?ric Germaneau >> >> College of Physical Sciences >> Graduate University of Chinese Academy of Sciences >> Yuquan Road 19A >> Beijing 100049 >> China >> >> Please consider the environment before printing this email. >> Consid?rez svp l'environnement avant d'imprimer cet email. >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum at pwscf.org >> http://www.democritos.it/mailman/listinfo/pw_forum >> >> > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > -- /Be the change you wish to see in the world / ? Mahatma Gandhi ? Dr. ?ric Germaneau <mailto:germaneau at gucas.ac.cn> College of Physical Sciences Graduate University of Chinese Academy of Sciences Yuquan Road 19A Beijing 100049 China /Please consider the environment before printing this email. Consid?rez svp l'environnement avant d'imprimer cet email. / -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110310/202e879a/attachment.htm
