Wrong DOS plot of graphene

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Seba Darshan
Posts: 63
Joined: Mon Feb 17, 2014 5:19 am

Wrong DOS plot of graphene

Post by Seba Darshan » Sat Aug 01, 2015 11:08 am

Dear Abinit Users

I have been trying for a while to obtain the density of states plot of graphene.
I have done the ecut and ngkpt convergence, then the optimization of atomic geometry of graphene and then tried to do density of states calculation using tetrahedron method.
I am facing a great problem that as per the theory the dos of graphene is zero at zero energy. But I am getting a different plot where the density of states is showing zero values away from the zero energy level. The input file, the dos plot and the output file are attached herewith.

Is it necessary that ngkpt grid should contain the high symmetry points of the Briolluin zone, how can I make sure that the grid contains these points. Is it the reason for the wrong result that I obtain.

Please guide me in this regard.

For my last two posts, I didnt receive a reply from anyone.

Please help me with some comments so that I could continue.

Thanks in advance
Seba
Attachments
dos.out
(51.05 KiB) Downloaded 355 times
dos.in
(440 Bytes) Downloaded 384 times
DOS of graphene.jpg
DOS of graphene.jpg (26.6 KiB) Viewed 5197 times

sheng
Posts: 64
Joined: Fri Apr 11, 2014 3:44 pm

Re: Wrong DOS plot of graphene

Post by sheng » Thu Aug 06, 2015 3:17 pm

May I know you perform parallel or serial calculation?

Seba Darshan
Posts: 63
Joined: Mon Feb 17, 2014 5:19 am

Re: Wrong DOS plot of graphene

Post by Seba Darshan » Sun Sep 13, 2015 11:06 am

sheng wrote:May I know you perform parallel or serial calculation?

Hai Sheng

Sorry for the delay in replying to the question.

I have done it in parallel using 8 processors. Does calculations in parallel can result in wrong results?

Hope to hear from you favourably
Thanks and Regards
Seba

sheng
Posts: 64
Joined: Fri Apr 11, 2014 3:44 pm

Re: Wrong DOS plot of graphene

Post by sheng » Sun Sep 13, 2015 12:23 pm

Two points:

1) Do DOS calculation in serial mode. I got wrong results previously using parallel mode, and if you browse through the forum you can also find people reporting about inconsistencies in its intensity.

2) Your fermi energy is -0.03430 Hartree. In your graph above did you shift your fermi energy to zero? From visual inspection, the DOS at fermi energy level is indeed zero.

en victory
Posts: 2
Joined: Mon Jan 07, 2019 2:02 pm

Re: Wrong DOS plot of graphene

Post by en victory » Sat May 11, 2019 8:14 am

Dear Seba Darshan,
I am a new user ABINIT. Have you get the solution of this problem?
Because I face same problem, but I can't get the solution.
Thank you.

ebousquet
Posts: 469
Joined: Tue Apr 19, 2011 11:13 am
Location: University of Liege, Belgium

Re: Wrong DOS plot of graphene

Post by ebousquet » Sat May 11, 2019 8:33 am

Dear en victory,
This is an old post from 2015, could you describe your problem and with which version of Abinit?
Best wishes,
Eric

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