[Pw_forum] Non Convergence

[BARRETEAU Cyrille]

I would also advise to increase nbnd since for magnetic system the default value is often too small.
I usually take nbnd=nelec/2*1.5 instead of the default value of nelec/2*1.2

Therefore you should take at least nbnd=80 instead of 60.

Cyrille
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Cyrille Barreteau
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________________________________________
De : pw_forum-bounces at pwscf.org [pw_forum-bounces at pwscf.org] de la part de Paolo Giannozzi [paolo.giannozzi at uniud.it]
Envoyé : jeudi 6 novembre 2014 17:45
À : PWSCF Forum
Objet : Re: [Pw_forum] Non Convergence

Metallic slabs are sometimes difficult to converge.
I tried with mixing_mod='local-TF' (works better for slabs),
a smaller mixing_beta (0.1), a larger degauss (0.05) and a
denser k-point grid (8 8 1) that should yield smoother results,
and it converges, at least for the reduced cutoff (30/300)
I tried.

Paolo


Try
On Wed, 2014-11-05 at 15:41 +0000, Elliot Menkah wrote:
> Hello Everyone,
> I'm running a geometry optimization calculation(relax) of an 11-layer
> Nickel slab and I used the deafult nstep (nstep=50) and electron_maxstep
> (100).
>
> My system did not converge with the parameters and configurations set as
> it run through 100 iterations.
>
> Could there be something wrong with the configuration or would I have to
> increase the  electron_maxstep value?.
>
> Please find attached both input and out files in that regard.
>
> Thank you
>
>
> Kind Regards,
>
> Elliot
>
>
>
>
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 Paolo Giannozzi, Dept. Chemistry&Physics&Environment,
 Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
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