Hello,
I'm here again to ask the same question. I built a system containing two Fe walls on the top and bottom with an epoxy network in between. The epoxy network was relaxed (optimization, annealing, NVT, and NPT, orderly) before "build layer" operation. After constructing the three layer model, I fixed the walls and ran geometry optimization, annealing, and NVT dynamics. Then, I used Perl script to apply an external force vertically to the top wall as the normal loading. However, different from other literature, my top wall always got deformed as shown in the screenshot. I wonder if that is due to my epoxy network was not fully relaxed, because I checked the epoxy network model after npt dynamics and found that the pressure of the system (about 0.028 GPa) was not around 0.0001 Gpa as what I set. And it could cause the uneven interaction between the top wall and the epoxy network and result in the clear deformation of the top wall? Please help me if anyone knows how to solve this problem. Really appreciate it.