[CP2K:2235] handling periodic images

[Teodoro Laino]

Nothing that you are missing Noam.. the only relevant thing is to check 
versus larger values of cutoff.
If this still does not work could you please send us an input file that 
shows this problem?
Teo

Noam Bernstein wrote:
> Hi - I'm running a simulation of a molecule with periodic boundary
> conditions, and I get rather large discrepancies between finite
> difference approximations of the force and the analytical forces.
> For a big unit cell (molecule is about 5x5x5 A, cell is 25x40x40),
> these discrepancies happen only for a few atoms, in a few cartesian
> directions.  In the process of trying to make a smaller test case, I
> found  that the discrepancies became much larger for a smaller unit
> cell, and affected all atoms and all directions.
>
> The only thing I can think of is something about how periodic images
> are handled (i.e. not just minimum image convention).  However,
> I've scoured the mailing list and documentation, but I can't find any
> mention of parameters that might affect the number of periodic
> images that are taken into account in various calculations
> (matrix elements, Ewald, maybe other things).  Is there something
> that I'm missing?
>
>                                                           Noam
>
> >
>