[gpaw-users] dipole correction

[Ask Hjorth Larsen]

Dear Misha

On Mon, 7 Jun 2010, Misha Monder wrote:

> Hello all,
>
> Do I need to include dipole corrections (added to the 0.7 release 
> version) for slab calculations that are not periodic in the z direction? 
> I am assuming no because the erroneous electric field is introduced only 
> when periodic boundaries are used. Am I correct in my understanding?
>
> Thanks.
>
> Cheers,
>
> Misha


There's *supposed* to be an electric field around a dipole, and that field 
must have a step - this step is incompatible with periodic (clearly) 
boundary conditions, but also with the non-periodic ones in GPAW because 
they are *zero* boundary conditions.

Therefore dipole correction is always "necessary" to describe a dipole 
layer.  But it may not be particularly important, depending on which 
quantity you are interested in.

Regards
Ask