forked from lijiext/lammps
64 lines
1.2 KiB
Plaintext
64 lines
1.2 KiB
Plaintext
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# sample LAMMPS input script for diffusion of 2d LJ liquid
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# mean-squared displacement via compute msd
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# settings
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variable x equal 40
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variable y equal 40
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variable rho equal 0.6
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variable t equal 1.0
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variable rc equal 2.5
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# problem setup
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units lj
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dimension 2
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atom_style atomic
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neigh_modify delay 0 every 1
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lattice sq2 ${rho}
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region simbox block 0 $x 0 $y -0.1 0.1
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create_box 1 simbox
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create_atoms 1 box
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pair_style lj/cut ${rc}
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pair_coeff * * 1 1
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mass * 1.0
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velocity all create $t 97287
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fix 1 all nve
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fix 2 all langevin $t $t 0.1 498094
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fix 3 all enforce2d
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# equilibration run
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thermo 1000
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run 5000
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unfix 2
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# data gathering run
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reset_timestep 0
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compute vacf all vacf
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fix 4 all ave/time 1 1 1 c_vacf[4] #file tmp.vacf
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# factor of 0.5 is for 2d
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fix 5 all vector 1 c_vacf[4]
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variable vacf equal 0.5*dt*trap(f_5)
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thermo_style custom step temp c_vacf[4] v_vacf
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# only need to run for 10K steps to make a good 100-frame movie
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#dump 1 all custom 1 tmp.dump id type vx vy vz
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#dump 2 all image 100 image.*.jpg type type zoom 1.6 adiam 1.2
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thermo 1000
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run 100000
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