Dear lammps users,
I am trying to use fix addforce to move a graphene layer in a block of polystyrene. I pull the graphene in one directoin and the polystyrene in the opposite direction.
I am getting the error "Cannot use variable energy with constant force in fix addforce"
I have read the comment on this error in the lammps manual many times but it does not point me in the right direction. I have tried modifying other commands in my script (below) that might effect energy but I continue to get the error. Perhaps I am missing the obvious but I could really use help at this point in understanding this error.
I have another question on this fix. Is it only implmented once in the script no matter how may steps are run? This would seem to make sense but it is not made clear in the manual.
Postdoctoral Research Associate
Rensselaer Polytechnic Inst.
Nanotechnology Center MRC 275A
110 8th St.
Troy, NY 12180