Dear all,
I am trying to simulate methane hydrate cage structure in lammps using NPT methods.
But I am facing problem with pressures. I am not getting stabilized pressure with
minimum fluctuation with in tolerance limit.
Please help me in this regard. I have pasted my input file. thanks in advance.
Thanks and regards,
Snehanshu
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512 + ONE METHANE 3X3X3 BOX
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units real
boundary p p p
atom_style full
bond_style harmonic
angle_style harmonic
pair_style lj/cut 10.0
pair_modify mix arithmetic
#kspace_style pppm/tip4p 1.0e-6
read_data A512str333final1.txt
pair_coeff 1 1 0.13389 3.166
pair_coeff 1 2 0.01716 2.61
pair_coeff 3 3 0.42566 3.35
pair_coeff 1 3 0.11767 3.258
bond_coeff 1 15.3299 0.9572
bond_coeff 2 4.97 0.9572
angle_coeff 1 0.0 109.52
angle_coeff 2 0.0 104.52
neighbor 2.0 bin
neigh_modify delay 0 every 1 check yes page 10000 one 1000
thermo 10
thermo_modify flush yes
minimize 1.0e-5 1.0e-7 1000 10000
dump 1 all atom 1000 dump.lammpstrj
dump_modify 1 flush yes
log run1.txt
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equilibration: NPT
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#unfix 2
fix 2 all npt temp 290.0 290.0 100.0 iso 30.0 30.0 5000 drag 10.0
timestep 1
run 50000
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dump atom positions for visualization, e.g. using VMD
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#timestep 1
#run 100000