Script to check Single layer graphene deformation in x direction

Hello everyone,

I have used quartic bond style as it uses the potential to define a
bond which can be broken . In the attached movie file the bonds are
getting broken but my concern here is the fracture should propagate by
a crack initiation .Am i missing a important check here? The data file
and script file are attached herewith also the simulation has been
done at 0 kelvin .The script uses lennard jones potential.

I am also self training on MD simulation as research and training
facilities are not present in India . I am from India and i am quite
new to lammps .
Sumit ,Nagar
M.Tech (Production engg)
B.E (Production and Ind Engg)
MCSA 70-290 ,SQL (Oracle z -007)
ITIL certified ,MCAD 70-306
GATE 2006,2013<div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br />
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Sumit ,Nagar
M.Tech (Production engg)
B.E (Production and Ind Engg)
MCSA 70-290 ,SQL (Oracle z -007)
ITIL certified ,MCAD 70-306
GATE 2006,2013