Stabilization Issue of Monolayer MoS2 with fix move command

Dear Sir,

I am a LAMMPS user since 2015. Currently, I am using LAMMPS 64-bit 23Oct2017 version right, and trying to analyze the van Dar Waals interaction between MoS2 and sapphire substrate. I strained the MoS2 a bit to make sure that the MoS2 layer and sapphire substrate have the same in-plane dimensions. The strained MoS2 is stable by itself. When I add the Al2O3 atoms, it loses its stability even though I assumed zero bonding energy for the LJ potential interaction between the MoS2 and Al2O3. I am using Stillinger-Weber potential for MoS2 layer and eam alloy potential for Al2O3 sapphire. I would appreciate if you could help me in resolving this issue.

Regards

Shiddartha paul

Department of Mechanical Engineering

Louisiana Tech University.

in.def (2.1 KB)

combined.lmp (42.5 KB)

Visualize your system. If the Al2O3 atoms are overlapping with your MoS2 atoms, then the simulation could be unstable.

Ray