Stress-strain behavior of bilayer graphene

Hello Axel,

Thank you for replying. Actually CVFF also uses morse potential. I am using the potential parameters for morse (in CVFF) for bond breaking. Actually, long time ago I started doing the simulation using harmonic potential and you suggested me to use morse instead.

Hello everyone,
I did MD simulation of a bilayer graphene in LAMMPS. The stress-strain
behavior of BLG didn’t seem to deviate from the single sheet. The fracture
stress of single sheet graphene was 167 GPa. And the bilayer fracture stress
are between 162-168 GPa. I am using CVFF potential for the simulation. When
I created my data file, I created two layers as two types of C atoms and set
up an interaction between type 1 and type 2 C atoms using lj/cut. The
parameters for lj/cut are same as I used between 1-1 interaction or 2-2
interaction. If I change the lj/cut parameters, then the bilayer strength
changes a lot. But that seems nonphysical to me. Can someone help me with
what I am doing wrong? Thank you very much. Here’s a part of my code:

i am confused by your use of the term “fracture”. how is it even
possible to “fracture” a model using CVFF? doesn’t it use harmonic
bond potentials, which cannot be broken?