32 lines
1.2 KiB
Python
Executable File
32 lines
1.2 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 DihedralTabulate
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################################################################################
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import math
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def harmonic_energy(phi):
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k = 100.0
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# the force constant in LAMMPS is in energy per radians^2 so convert from degrees to radians
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deg2rad = math.pi / 180.0
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f = k * (1 - math.cos(2.0 * deg2rad * phi))
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return f
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################################################################################
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if __name__ == "__main__":
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dtable = DihedralTabulate(harmonic_energy, units='metal')
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dtable.run('HARM')
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