Dear Lammps users,
Hello,
I have 2 question;
1-What is a convenient damping factor for “fix langevin” command, in real units… in a system with temperature is around 250 k. ( the time step is 2 fs).
could we set it at 1000?
2-What is a convenient accuracy for ewald style in k-space cpmmand in real units…
could we use 1e-03 in a scientific work?
Many thanks in advance,
SIMIN
Dear Lammps users,
Hello,
I have 2 question;
1-What is a convenient damping factor for "fix langevin" command, in real
units.... in a system with temperature is around 250 k. ( the time step is
2 fs).
could we set it at 1000?
what is a good parameter depends on your system. there is no such
thing as a globally "best" or "safe" value.
2-What is a convenient accuracy for ewald style in k-space cpmmand in real
units..
could we use 1e-03 in a scientific work?
most likely not. please note that this is a unitless parameter. again,
it depends very much on your system and what level of accuracy you (or
your reviewers) consider sufficient for the analysis/results you
present. please note that the estimator algorithm used in LAMMPS is
based on assumptions of a dense system of charged point particles
(e.g. bulk water).
axel.
A good rule of thumb for fix langevin is 100 timesteps for
the damping factor. You’ll have to express that in
whatever your time units are.
Steve