Dear all
I am trying to replicate the results of the following paper (10.1103/PhysRevLett.93.016001) to understand the process of athermal quasi-static shear deformation. I am using LAMMPS version (lammps-patch-17feb2022) to perform my simulations.
I am using pair_style harmonic/cut with value of K equal to 1 to mimic a soft-potential as mentioned in the paper. The packing fraction is 1.0. I am using conjugate gradient method to minimize the forces and energy of the system. While doing so , instead of reaching the force tolerance criteria as mention in the code , the simulation is getting stopped with the criteria linesearch alpha is zero. Can anyone give me suggestion to understand the mistake I am doing. Any suggestion to solve this problem is appreciated. I have also attached the simulation code I am using for the same.
Regards
Divas
Minimization stats:
Stopping criterion = linesearch alpha is zero
Energy initial, next-to-last, final =
72153.432573231 39512.8547171024 39512.8547171024
Force two-norm initial, final = 178.05505 40.280413
Force max component initial, final = 3.3438459 1.012577
Final line search alpha, max atom move = 5.7464705e-12 5.8187437e-12
Iterations, force evaluations = 62 108
units si
atom_style sphere
dimension 2
region box prism 0.0 200.0 0 200.0 -0.5 0.5 0.0 0.0 0.0
region particle prism 0.0 200.0 0.0 200.0 -0.5 0.5 0.0 0.0 0.0
create_box 2 box
create_atoms 1 random 38205 3000 particle units box
create_atoms 2 random 47225 4000 particle units box
set type 1 diameter 1.0
set type 2 diameter 0.52
pair_style harmonic/cut
pair_coeff * * 1.0 1.0
compute fcl all property/local patom1 patom2
compute fc all pair/local dist force
compute peratom all stress/atom NULL pair
compute p all reduce sum c_peratom[1] c_peratom[2] c_peratom[3] c_peratom[4]
variable press equal -(c_p[1]+c_p[2])/(2*vol)
variable sigmaxy equal c_p[4]/vol
fix 2 all enforce2d
thermo 100
thermo_style custom step ke pe v_press v_sigmaxy
dump mydump all atom 100 stiffness_1.dump
dump 1 all custom 100 *.data id type diameter mass x y z vx vy fx fy
dump_modify 1 sort id
min_style cg
restart 100 restart.*.stiff_1
minimize 0.0 1.0e-10 1000000 10000000
