I beg to slight differ. It does not make much sense to assign a “default value” 
to the Gaussian smearing, unless one makes sure that the computations are well 
converged with respect to the number of k points, for that specific value of 
the smearing. The rational procedure to follow is: 1) start with whatever value 
of the smearing one wishes, and make sure that the (internal, *not* “fake 
free”) energy is well converged with respect to the number of k points. If the 
number of k points is sufficient, it is likely that no nasty oscillation would 
arise; 2) decrease the smearing and vary the number of k points accordingly. 
HTH — Stefano B


—
Stefano Baroni -  SISSA, Trieste - http://stefano.baroni.me, stefanobaroni 
(skype)

I do not mind if you think slowly, but I do object when you publish more 
quickly than you think [W.E. Pauli to an unknown colleague, as reported by N. 
Kemmer]

> On 25 Jan 2021, at 15:08, Lucas Nicolás Lodeiro Moraga 
> <[email protected]> wrote:
> 
> Hi, 
> It appears a metallic oscillation, where a couple or more states change their 
> relative energy, and change their energetical order, then the occupation 
> changes abruptly (non continuous). If this is the problem, it is better to 
> increase the degauss value and/or change the smearing method.
> Typically I use methfessel-paxton with 0.015 Ry for degauss, which mimics the 
> VASP default values. When you get a converged system, you can try to decrease 
> (slowly) the degauss.
> 
> Regards - Lucas Lodeiro
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