[Wien] energy scale zero and average IS-potential

[Peter Blaha]

On Tue, 22 Jun 2004, David Sedmidubsky wrote:

> Dear WIEN2k users,
> In Wien Archives I found that the energy scale for DOS and Ef should be
> referred to the average potential in the interstitial region which
> defines the zero energy. If it is a volume average, it should be equal
> to V(Gama) component of the potential Fourier expansion given in
> case.vtotal. Thus I would expect that I can get the work function by
> taking V(Gama) and adding Ef to it. For metal aluminium I get
> V(Gama)=-0.708 Ry and Ef=0.538 Ry, resulting in a work function 2.31 eV
> compared to experimental 4.28 eV. Even worse, for most actinide
> compounds I calculated, Ef would lie above vacuum level (provided
> potential is referred to that level).

For workfunctions you must do a surface calculation with a "slab-geometry"
and sufficient vacuum region. WIEN2k will even print the :VZERO

I think this is in the UG ... ?

                                      P.Blaha
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Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
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Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
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