[Wien] about the fermi level

[Andrei Postnikov]

On Tue, 28 Oct 2003, Yushan Wang wrote:

| DEAR USERS:
|
| for pure TiO2, its total valence band is below the fermi level as it
| should be for a semiconductor.

Right.

| for a nitrogen doped TiO2, it should be  a semiconductor too,

If this is indeed so in reality, it might be due to
non-stoichiometry, or the presence of other charge-compensating defects.
(Sorry, I have no previous knowledge about N-doped TiO2).

| but the calculated DOS shows that some valence bands
| are above the fermi level. who know why?

You probably simply substitute a (hopefully small) number or your O by N,
so the Fermi level slightly displaces away from the gap, what's wrong?

Best regards,

Andrei Poostnikov
 +-- Dr. habil. Andrei Postnikov ----- Tel. +49-541-969.2377 -- Fax .2351 ---+
 | Universitaet Osnabrueck - Fachbereich Physik, D-49069 Osnabrueck, Germany |
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