Is there a way to use a fix press/berendsen in a ReaxFF simulation? Because everytime I try to start the MD pressure and volome are set to nan. I also looked at the atoms, and they vanish in the second timestep. A npt simulation works fine. I use the following code
# (1) Initialisierung
You can use either pressure control (npt, berendsen) with
any potential in LAMMPS. If you're saying that the initial
pressure (time 0) is Nan with Bernedsen and a good value
with fix npt, that shouldn't happen, b/c the pressure fix
hasn't done anything yet. If that's what you're seeing
then please post a sample input script/data file that
shows this.
Your fix npt and berendsen commands below have NULLs
in them, which is not valid. LAMMPS is probably reading
those as 0.0 which may or may not be what you want.
Older versions of LAMMPS used NULLs as options in these
commands, but the current version does not. And your syntax
isn't even right for the older version, I don't think.
So fix that first, as it may be affecting the bigger issue.
Steve