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Hi
I have a basic question about integrated dos. I have a semiconductor, so the level above fermi level should be empty.
well, which one is the meaning of integrated dos?
1. the number of electrons in unit cell?
or 2. the number of states (occupied and unoccupied) in unit cell?

if the first is correct, why the integrated dos has share above the fermi level?
if the second is correct, why the number of state(occupied and unoccupied without regarding to fermi distribution) are equal sum of the number of valence electrons of atoms in unit cell? may the number of all states normalized to total number of valence electrons?

thankful.

Hi,

The integrated DOS is the total number of states, occupied and unoccupied, in the unit cell.
It is integrated up to the number of bands calculated.

If you don't set the variable "nband", the code will only compute the occupied bands, plus maybe a few. So it is likely that the integrated DOS won't go very far above the fermi level.
Simply look at the value of "nband", echoed in the output file, and set it to some higher value in the input file.

Best regards!

Hi
Ok. Thank you very much.

Hi again.
Just two question .1- Why the sum of PDos isn't equal to total Dos?
2-The PDos is Projected Dos but what is partial Dos?
Thanks again.

The projected DOS, or partial DOS is computed by projecting each wave function on a specific angular momentum around a specific atom, within some atomic radius.
Hence, even if you include all possible angluar momentum around all atoms, the sum of the partial DOS will never be exactly the total DOS, since the spheres do not cover the entire unit cell.
See the description of the input variable "prtdos" for prtdos = 3.

Cheers!

Hi dear gabriel.antonius
I'm sorry be late. Thank you for your reply. It was realy helpful .
Are you mean, there are some eignfunctions of crystall that aren't included in sphere around atoms so it's wave vectore isn't calculated in pdos correspondingly?

All wavefunction extend beyond the atomic sphere.
Typically, occupied states and the first few unoccupied states have strong atomic character, that is, they are very localized around atoms and have one major angular momentum projection. As you go to higher state, they start to be more delocalized and more "free electron" shaped.
In the PAW formalism, some part of the wavefunction is computed on a localised basis inside atomic sphere, and the other part is described by plane waves.
Only the former is used to calculate the pdos. Thus, there is always some part of the wavefunction left away, either because it projects on an other angular momentum not included in the calculation, or because it is too far from the atoms for an angular momentum decomposition to be meaningful.

dear gabriel.antonius thanks.