The Fermi level is normally calculated by setting the cumulative occupation
number of all bands to the number of valence electrons.
As I understand this means that Ef in semiconductor would always be
at the VBM and not in the middle of the gap?
How it could happen that Ef appeared somewhere in the middle of the gap
in my calculations (see my previous post)?
There are no states in the gap independently on the amount of k-points.
By the way, how the bandstructure is calculated using only several k-points?
In a metal system, metal Etot won't be so stable against
k-mesh as in semiconductor, and would normally require much much more
dense k-mesh.
Well in my case of partially filled dangling bonds on the surface I end
up as a metallic system.
Would Methfessel-Paxton smearing help in my case?
Again, does population of the bands affect the band structure and total
energy or population is a secondary property? - see my example of
molecule adsorption to dangling bond in previous post.
> It would be such a good investment to add a tetrahedron integration
> in Siesta... And a not very difficult one...
From my experience one needs about 10*10*10 mesh nodes along each
direction in BZ to get convergence with tetrahedrons.
Does one need that much points for metals?
I don't see the problem of SCF convergence in my bulk GaAs.
I see that Ef(k-points) doesn't converge (up to 50A).
I think that 4000 k-points is more than enough for convergence even for
metals. But I don't see convergence at all even for more k-points.
Thanks,
Alexander
