[Pw_forum] scf convergence of defected hBN

[lt15]

I see. I tried it and it converges now. Thanks!

best,
Lei

>
> Paolo Giannozzi Wed, 27 Dec 2017 09:18:39 -0800 You should add a  
> smearing, even if you think that your system is not
> metallic (if you think it is, you MUST add a smearing). Something like
> occupations='smearing', smearing='gaussian', degauss=0.01 to 0.05 or so.
> You might also try a spin-polarized calculation.
>
> Paolo
>
> On Wed, Dec 27, 2017 at 3:51 AM, lt15 <l... at rice.edu> wrote:
>
>>
>> Hi
>>
>> I was doing a 'scf' calculation for a defected h-BN structure as shown in
>> the attached figures. I would like to obtain the charge density of the
>> layer especially around the defect. But I found the calculation couldn't
>> converge as the 'estimated scf accuracy' in the output file keeps
>> fluctuating. In the input file, I tested different mixing_mode like 'plain'
>> and 'local-TF'. or the mixing_beta value like 0.01. 0.1, 0.3, 0.7. But
>> still, it didn't converge even after 8 hours running. In structure in-a,
>> the defected boron atom was far away from its original lattice position, as
>> shown in in-a.png. In structure in-b, the defected boron atom plus a
>> nitrogen atom around the edge of layer were deleted, as shown in in-b.png.
>> In structure in-b, the layer still maintained neutral electricity and kept
>> the void defect in the center. However, neither structure can converge.
>> Could you give some suggestions about the convergence issue for this
>> defected structure? Thank you.
>>
>> best,
>> Lei
>>
>> _______________________________________________
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
>
> -- 
> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
> Phone +39-0432-558216, fax +39-0432-558222
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum