[DFTB-Plus-User] Bandgap of GNR

Gabriele Penazzi penazzi at uni-bremen.de
Wed Jan 13 10:41:17 CET 2016

Hi Kazuma,

you don't need k-points in x direction here. I've run your input with
the supercell folding set to 1 in x direction (left 25 in y). I lowered
the force tolerance to 1e-3 too (didn't want to wait too long) and I get
1.42 eV (detail of dos around gap attached). Your structure seemed not
optimized but this should not be the problem, even if I run the input as
it is with the geometry you sent but removing optimization I get
something around 1.3 eV. Maybe you do some mistake when evaluating the gap.


On 01/13/2016 10:04 AM, u3129004 at edu.gifu-u.ac.jp wrote:
> Dear DFTB+ user,
> I calculated Density of states of graphene nanoribbon (please refer to 
> an attached file). But I am doubtful of this result. Because the bandgap 
> is a lot different from other calculation results which are calculated 
> by Tight Binding method and first principal calculation. I attached my 
> input file for this calculation.
> It would be very helpful if you could provide me any advice.
> Thank you in advance,
> Kazuma
> ---------------------------------------------------
> Kazuma KIHIRA
> Environmental & Renewable Energy Systems Division
> Graduate School of Engineering, Gifu University
> E-mail:u3129004 at edu.gifu-u.ac.jp
> ---------------------------------------------------
> _______________________________________________
> DFTB-Plus-User mailing list
> DFTB-Plus-User at mailman.zfn.uni-bremen.de
> https://mailman.zfn.uni-bremen.de/cgi-bin/mailman/listinfo/dftb-plus-user

Dr. Gabriele Penazzi
BCCMS - University of Bremen

phone: +49 (0) 421 218 62337
mobile: +49 (0) 151 19650383
-------------- next part --------------
A non-text attachment was scrubbed...
Name: dos.jpg
Type: image/jpeg
Size: 27042 bytes
Desc: not available
URL: <http://mailman.zfn.uni-bremen.de/pipermail/dftb-plus-user/attachments/20160113/add33268/attachment-0001.jpg>

More information about the DFTB-Plus-User mailing list