[Pw_forum] scf

[Stefano de Gironcoli]

dear Alvaro
 
  0.003 Ry is about 50 meV ... a very small value, and 0.001 is even 
smaller. this will require almost and infinity of  k-points in order  to 
obtain converged results... and such a small value may make scf 
convergence very difficult (unless very many k-points are used) because 
from one  iteration to the next the occupation of levels can suddenly 
change in a non-linear way making the mixing scheme ineffective...
are you sure you need such a small value of degauss ?

 stefano de Gironcoli - SISSA and DEMOCRITOS

Álvaro Alves wrote:
> Hello I am doing a scf calculation system and uses degauss = 0.003 and 
> needed change it paar 0001. With this new value, the calculation does 
> not converge. What may be happening?
>
> Regards, Alvaro
>
>
>
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