[Pw_forum] Two vacuum energies with dipole correction

[Ari P Seitsonen]

Dear Niharika Joshi,

   My quick answer, the relaxed surface is more realistic, that's why I 
would take the value at that side.

   Regarding the comment about "something close to the experimental value" 
of the work function, it is known that the absolute value of the clean 
surfaces are often of the order of 0.5 eV wrong (too low, if I remember 
correctly) with the GGA functionals compared to the experimental values: 
One of the famous short-comings of these functionals; funnily enough LDA 
is often closer to the experiments, if I remember correctly.

     Greetings from Zurich,

        apsi

-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
   Ari P Seitsonen / Ari.P.Seitsonen at iki.fi / http://www.iki.fi/~apsi/
   Physikalisch-Chemisches Institut der Universitaet Zuerich
   Tel: +41 44 63 54 497  /  Mobile: +41 79 71 90 935


On Mon, 15 Apr 2013, N H Joshi wrote:

> Dear Ali,
> 
> Thanks a lot for your reply.
> 
> The work function value that I get without the dipole correction is 4.9 eV
> and the with dipole correction I get 5 eV and 4.8 eV if I take lower and
> higher potential value
> in the vacuum region.
> 
> And I couldn't follow what you meant by 'without mixing_mode'.
> Won't the code take the default mixing_mode? And how does it help in this
> case?
> 
> With regards,
> Niharika Joshi
> Project student,
> Department of Physics,
> IISER, Pune
> India.
>