Thank you all for your suggestions. I think the best move would be to
increase the smearing value until I achieve convergence. I also wanted to
ask, but would mixing = 'local-tf' be a good mixing method for this system?
The crystal has been confirmed experimentally to be a metal, and I the
We do not necessarily disagree. The internal energy is harder to converge than
the free energy, because the first is not variational, whereas the latter is
so. Also, level crossing is obviously much reduced (and eventually eliminated)
for large enough smearing. S.
> On 25 Jan 2021, at 16:59,
Dear Stefano, Lucas,
this is one of the few areas where I disagree with Stefano - I think we
should use the free energy (forces and stresses are the total derivative
of the free energy, not the internal energy), and that level-crossing
instabilities are exceedinfly difficult to cure with
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
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.