Thanks for the quick response.
After some further testing with the latest version, 15 May 2015, the issue still occurs, but I have narrowed the issue down a bit. I have found that when doing a simple minimization of a non-equilibrium structure, the results are consistent between simulations. Also, if I manually randomize the positions (when creating the sample) and then minimize that structure the results are consistent. The trouble comes when I use MD to randomize the positions, although the discrepancy between simulations is smaller now. Now to answer your questions, Axel
1.7 angstrom cutoff where and how? have you seen this statement in
the airebo docs?
What I mean to say is that I used the as provided CH.airebo file, with rcmin_CC 1.7, being the cutoff to which I was referring.
For each type pair (C-C, C-H, H-H) the cutoff is obtained by
multiplying the scale factor by the sigma value defined in the
potential file for that type pair. In the standard AIREBO potential,
sigma_CC = 3.4 Angstroms, so with a scale factor of 3.0 (the argument
in pair_style), the resulting E_LJ cutoff would be 10.2 Angstroms.
My pair_style command is as follows:
pair_style airebo 0.0 0 0
pair_coeff * * CH.airebo C
Using the following didnt change the results significantly,
pair_style airebo 3.0 0 0
pair_coeff * * CH.airebo C
Thanks again for your help and insight.
Thanks for the quick response.
After some further testing with the latest version, 15 May 2015, the issue
still occurs, but I have narrowed the issue down a bit. I have found that
when doing a simple minimization of a non-equilibrium structure, the results
are consistent between simulations. Also, if I manually randomize the
positions (when creating the sample) and then minimize that structure the
results are consistent. The trouble comes when I use MD to randomize the
positions, although the discrepancy between simulations is smaller now. Now
to answer your questions, Axel
1.7 angstrom cutoff where and how? have you seen this statement in
the airebo docs?
What I mean to say is that I used the as provided CH.airebo file, with
rcmin_CC 1.7, being the cutoff to which I was referring.
parameters in the potential file should better not be changed. they
are not entirely independent.
For each type pair (C-C, C-H, H-H) the cutoff is obtained by
multiplying the scale factor by the sigma value defined in the
potential file for that type pair. In the standard AIREBO potential,
sigma_CC = 3.4 Angstroms, so with a scale factor of 3.0 (the argument
in pair_style), the resulting E_LJ cutoff would be 10.2 Angstroms.
My pair_style command is as follows:
pair_style airebo 0.0 0 0
pair_coeff * * CH.airebo C
that would actually be what the docs refer to as pair_style rebo.