Dear LAMMPS users,
I am doing two-dimensional MD simulations of LJ particles in NVT. By using fix addforce command, we have applied a constant force on only one particle in the system. But we are getting a drift of all the particles though the value of the constant force is very small. Can you please help with that matter?
This behavior is expected. Due to the interactions between particles the one particle you add a force to will drag others along and they will gradually accelerate.
If you don’t want that to happen, you have to restrain the other atoms in some way, e.g. by using fix spring or by adding a “counterforce” on all other atoms.