39 lines
1.3 KiB
Python
Executable File
39 lines
1.3 KiB
Python
Executable File
#!/usr/bin/env python
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# ----------------------------------------------------------------------
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# LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
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# https://www.lammps.org/ Sandia National Laboratories
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# LAMMPS Development team: developers@lammps.org
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#
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# Copyright (2003) Sandia Corporation. Under the terms of Contract
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# DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
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# certain rights in this software. This software is distributed under
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# the GNU General Public License.
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#
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# See the README file in the top-level LAMMPS directory.
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# -------------------------------------------------------------------------
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from tabulate import PairTabulate
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################################################################################
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import math
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epsilon = 1.0
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sigma = 1.0
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def lj_energy(r):
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f = 4.0*epsilon*(math.pow(sigma/r,12.0) - math.pow(sigma/r,6.0))
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return f
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def lj_force(r):
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epsilon = 1.0
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sigma = 1.0
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f = -4.0*epsilon*(-12.0*math.pow(sigma/r,12.0)/r + 6.0*math.pow(sigma/r,6.0)/r)
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return f
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################################################################################
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if __name__ == "__main__":
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ptable = PairTabulate(lj_energy, lj_force)
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ptable.run('LJ_11')
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epsilon = 1.0
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sigma = 1.5
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ptable.run('LJ_12')
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