adhesive force and separation between zinc oxide and graphene

Hello everyone,
I am using the lammps to simulate the zinc oxide and graphene by following a paper (Molecular dynamics prediction of interfacial strength and validation through atomic force microscopy). I want to obtain the relationship of force and displacement (distance between zinc oxide and graphene) shown in fig.1 of the paper. However, the figure I got was so different with the one shown in that paper. I am not sure where the mistakes are. Also, Can you tell me the difference between force and stress of atom and how to calculate them? I attached my input file (move2), log file (output), and the figure I got. Please help me. Let me know if you have any question. Thank you so much!

figure i obtain.xlsx (78.7 KB)

Molecular dynamics prediction of interfacial strength andvalidation through atomic force microscopy.pdf (912 KB)

move2 (1.51 KB)

output (98.7 KB)

restart.npt_nvt1 (315 KB)

Sorry, no one is likely to read a paper and your input script
and tell you how to modify your script to match the paper.
That is a job for you and your advisor.

If you are asking the difference between force and stress,
then you need to do some basic study on MD and atomistic
values and read the corresponding doc pages for the LAMMPS