Re: [ESPResSo-devel] harmonic potential

[Burkhard Duenweg]

Hello,

I think Markus' remarks are very enlightening, and
probably an excellent suggestion.

Let me add: In my opinion, the ONLY reason why you
would like to have harmonic bonds available, to begin
with, is this: Gaussian chains have the notorious
advantage that you can solve some problems for them
analytically. I.e. they are good candidates for various
tests - for example, if you implement a shear flow
without hydrodynamic interaction and want to compare
with the Rouse model. For a Gaussian chain, you can
do this fully quantitatively. But there should be no
intrinsic necessity to run such a test in a parameter
region where the program fails, for parallelization
reasons.

Some atomistic potentials include harmonic bonds, but
these are usually so stiff that one should never-ever
run into such "fluffiness" problems.

BTW: A strictly Gaussian chain has ZERO r_0!!!

Regards Burkhard.

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