[MMTK] Ewald sums.

Konrad Hinsen hinsen@cnrs-orleans.fr
Mon, 10 Sep 2001 16:30:50 +0200


> For example, after loading python:
> -----
> >>> from MMTK import *
> >>> universe = load("water.univ")
> >>> universe.energy()
> 1077872366.1194236
> >>> from MMTK.ForceFields import Amber94ForceField
> >>>universe.setForceField(Amber94ForceField(15.*Units.Ang,
> 15.*Units.Ang))
> >>> universe.energy()
> -33920.758650668249

Can you print the result of universe.energyTerms() for both cases?
This does look a bit strange, in general the energy with Ewald
summation is not very much different from the value obtained with a
sufficiently large cutoff.

Konrad.
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