Hello,
I have some basic questions about the band structure, e.g., graphene.
Plz, see the attached input file (.fdf) and the .bands file generated by 
siesta. The dispersion agrees with the previous work. Now I want to calculate 
the Fermi velcity of Dirac electrons. I can see a linear dispersion around K.
1. How can I use the .bnds file to calculte the Fermi velocoity. Plz, use the 
attached file and explain me. I never did it and its very crucial, minor 
mistake can give me very bad result
2. When I use a big supercell then the band structure of this supercell is 
different from the promitive graphene. How can I reproduce the band structure 
of primitive form the supercell. In principle the band structures should be the 
same except the number of bands.

Regards,
Mic



________________________________
 From: I. Camps <[email protected]>
To: somayeh fotohi <[email protected]>; "[email protected]" 
<[email protected]> 
Sent: Monday, July 29, 2013 3:19 PM
Subject: Re: [SIESTA-L] systemlable.band.up and systemlable.band.down
 


Dear  Somayeh,


Attached is a modified version of gnubands program (I called gnuband_spin). It 
is capable to produce two separate files for the spin up/down bands.

Usage: ./gnubands_spin input_file output_up output_down, were: 

"input_file": is you band file

"output_up": is the desired name for the file with the bands for the spin up 
configuration 

"output_down": is the desired name for the file with the bands for the spin 
down configuration


What I did was to duplicate the code in the original gnuband: the first part 
save the UP configuration, and the second w«one, save the DOWN configuration.


Good luck!


On Sun, Jul 28, 2013 at 7:54 AM, somayeh fotohi <[email protected]> wrote:

Somayeh




[]'s,

@mps

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