[Wien] unoccupied DOS continuum states

[Lamoen Dirk]

Dear Wienusers,
we calculate the unoccupied DOS at high energies (up to 70 eV above the Fermi level)because we are interested in the excitation spectra. Our results are systematically too low at high energies compared to experiments and to calculations with a hydrogenic model.
Possible reasons for the discrepancy are :
* DFT is not suited for excited states.
* the (L)APW+lo basis set is only good in a limited energy region. 

Do you agree with this point of view ? 

Can the terminology of "continuum states" which is often used within a hydrogenic model description of the spectra still be used within a solid state description with periodic boundary conditions ? We feel that this concept is still useful though not well defined. 

Best regards,

Kevin Jorissen   Dirk Lamoen
   
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Dirk Lamoen
Departement Natuurkunde|Department of Physics
Universiteit Antwerpen|University of Antwerp
Campus Middelheim
Groenenborgerlaan 171
B-2020 Antwerpen
Belgium
tel : +32-(0)3-2653316
fax:  +32-(0)3-2653318
email: Dirk.Lamoen at ua.ac.be
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