[lammps-users] Constant velocity and Box Size

Hi All,

I am trying to move atoms at the boundary with a constant velocity, with fix setforce set to zero for x,y,and z. (for applying a strain rate).
Though my coordinates at the boundary are properly getting updated every timestep, but the box dimension only gets updated at some interval say after 5000 or 10000 time steps depending on the applied velocity. (usually it gets updated when box get extended by 1 angstroms in Z direction (direction of strain).

My question is why the box size is not getting updated every timestep ?

Thank you


Not sure what you are asking, but if you are using shrink-wrap
boundaries, then the box will be re-fitted around the atoms.
This does not happen every step, but on reneighboring steps.
But "when" it happens shouldn't matter to your simulation,
b/c the box size is artificial in this case, and LAMMPS will correctly
capture all the atom-atom interactions at every step.