48 lines
799 B
Plaintext
48 lines
799 B
Plaintext
# Steinhardt-Nelson bond orientational order parameters for BCC
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variable rcut equal 3.0
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boundary p p p
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atom_style atomic
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neighbor 0.3 bin
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neigh_modify delay 5
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# create geometry
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lattice bcc 1.0
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region box block 0 3 0 3 0 3
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create_box 1 box
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create_atoms 1 box
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mass 1 1.0
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# LJ potentials
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pair_style lj/cut ${rcut}
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pair_coeff * * 1.0 1.0 ${rcut}
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# initial velocities
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velocity all create 5.0 482748
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fix 1 all nve
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# 8 neighbors, perfect crystal
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compute qn all orientorder/atom degrees 5 4 6 8 10 12 nnn 8
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compute avqn all reduce ave c_qn[*]
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thermo_style custom step temp epair etotal c_avqn[*]
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run 0
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# 14 neighbors, perfect crystal dynamically melting
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uncompute qn
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compute qn all orientorder/atom degrees 5 4 6 8 10 12 nnn 14
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timestep 0.003
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thermo 1
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run 20
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