difference between wannier total dipole and berry total dipole

[labicia]

Good morning!

We are kind of new on this subject: may somebody tell us in a few words the 
difference between the wannier total dipole and berry total dipole.
Or at least give us some reference to document ourselves?

We are simulating a periodic bulk of methane.
Are both methods suitable for this kind of system?

The trend of the wannier total dipole and berry total dipole are almost the 
same, apart for a rescaling factor (total_wannier = 4.5 * total_berry + K), 
with K a constant.

Thank you very much,
and be patient if the question is a bit trivial,
Marco and Andrea
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20131024/b68ea648/attachment.htm>