[gmx-users] PME question

[Marc Baaden]

Hi Erik (and all others on this thread),

lindahl at stanford.edu said:
>> Well, imagine you have a charge -1 in the center of the box, and +1
>> next  to one of the box sides. This will give you a net dipole in the
>> system. Now, if the +1 charge moves across the box boundary and
>> reappears on the other side the dipole will suddenly have the opposite
>> direction after a discrete instantaneous jump. 

I think that's a very interesting point, although I guess that as the dipole
depends on the distance between the charges, the effect should be quite small
if the box is 'reasonably sized' (maybe >3 nm ?).
Is there any more systematic analysis of that kind of problem/artefact ?

  Marc


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 Dr. Marc Baaden - Laboratory of Molecular Biophysics, Oxford University
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