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Should the integral of the partial DOS (projected on a particular type of orbital at one atom) over all the energies (below and above the Fermi level) be a constant?

For example, if I am comparing the electronic structure of an atom in two different oxidation states: when I have less partial DOS below the Fermi level, should I have then necessarily more partial DOS of the same type above the Fermi level?

I am asking because of this: I am projecting the DOS on the levels of one particular atom interacting with a surface. The s level of the adatom is mainly occupied in the isolated neutral atom, but it is mainly empty when interacting with the surface, showing that the adatom has oxidised. I can see this very clearly in one particular configuration of adsorption. This interpretation agrees well with the positive (Bader) charge of the atom, and with the observation of simultaneous reduction of another atom at the surface.

However, in a different adsorption configuration, although everything is again indicating the oxidation of the adatom (Bader charges and the electronic occupation of other atoms), the peak above the Fermi level indicating the oxidation of the adatom is not present. I don't seem to have an increased s DOS below the Fermi level. Neither there are empty peaks corresponding to other orbitals of the same atom. So I cannot really understand why I not see any empty levels for this atom if it has oxidised...

Any help?

please check if the energy grid on which you calculated the DOS (NEDOS) is fine enough to resolve all peaks properly. Maybe this peak is just so narrow that it does not show up in your plot.
To check whether the expected levels exist or not, please have a look at the PROCAR file (thereby you can also anticipate the width of the peak by having a look at the dispersion of the respective states) .

Better still, just calculate your DOS integrals from your PROCAR file.

The integral of your total DOS (or total charge density) around any particular atom should be more or less constant regardless of the oxidation state, but wouldn't be sure about the individual "orbitals". Who tells you which orbital belongs to which atom?
<span class='smallblacktext'>[ Edited Fri Apr 10 2009, 07:17AM ]</span>