[Pw_forum] How to improve the DOS plot?

[Rolly Ng]

Dear Cyrille,

Yes, you are right! I kept broadening to 0.002 Ry in my dos input and 
while I increase that to 0.02 I get the smoothed DOS plot.

Need not nscf recalculation.

Thank you very much,

Rolly


On 07/22/2016 03:34 PM, BARRETEAU Cyrille wrote:
> Dear Rolly
>
> I guess you are using a very small broadening to plot your DOS.
> You should increase it to get smoother curves.
>
> good luck
>
> Cyrille
>
> ========================
> Cyrille Barreteau
> CEA Saclay, IRAMIS, SPEC Bat. 771
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> ========================
>
> ________________________________________
> De : pw_forum-bounces at pwscf.org [pw_forum-bounces at pwscf.org] de la part de Rolly Ng [rollyng at gmail.com]
> Envoyé : vendredi 22 juillet 2016 09:10
> À : PWSCF Forum
> Objet : [Pw_forum] How to improve the DOS plot?
>
> Dear QE experts,
>
> I have managed to do spin polarized calculation on gold-doped graphene
> supercell with total of 72 atoms. There are 71 carbon atoms and 1 gold
> atom at the center of the supercell.
>
> I did scf with 6x6x1 (automatic) k-points, then nscf with 6x6x1 and
> 12x12x1 (automatic) k-points respectively. I believe the denser the
> k-points, the better the DOS plot. Then I did dos.x and it produced the
> plot.
>
> However, I found there are lots of noise (oscillations) in the DOS in
> comparison to the 6x6x1 k-points we did previously with DMol3. The DMol3
> is much smoother than that of QE v5.3.0. I am attaching both output
> plots, how can I improve the smoothness of the DOS plot?
>
> I know increasing the k-points for nscf calculation does help but it
> take 120GB of RAM to run 12x12x1 and it is impossible to increase the
> k-point density indefinitely.
>
> Thanks for your advice,
> Rolly
>
> --
> PhD. Research Fellow,
> Dept. of Physics & Materials Science,
> City University of Hong Kong
> Tel: +852 3442 4000
> Fax: +852 3442 0538
>
>
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-- 
PhD. Research Fellow,
Dept. of Physics & Materials Science,
City University of Hong Kong
Tel: +852 3442 4000
Fax: +852 3442 0538