Dear LAMMPS users,
I tried to ramp up stresses, normal stress sigma_yy and sigma_zz, of my system using NPT. From my first run, the stress curves showed that the stress components are constant, i.e. they didn’t change with time after roughly 130 ps. However, the plateau of stress was not my target stress. For some reason, I restarted my simulation with exactly the same given stresses using NPT. Then I saw relaxation of my system immediately when my second run started and stress components reached the target values.
I have two questions:
Q1. Why cannot my system reach the target stresses in my first run?
Q2. Why can my system get relaxed further in my second run?
The version of LAMMPS I’m using is LAMMPS (29 Oct 2020).