70 lines
1.3 KiB
ReStructuredText
70 lines
1.3 KiB
ReStructuredText
.. index:: dihedral_style fourier
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.. index:: dihedral_style fourier/intel
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.. index:: dihedral_style fourier/omp
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dihedral_style fourier command
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==============================
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Accelerator Variants: *fourier/intel*, *fourier/omp*
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Syntax
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""""""
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.. code-block:: LAMMPS
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dihedral_style fourier
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Examples
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""""""""
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.. code-block:: LAMMPS
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dihedral_style fourier
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dihedral_coeff 1 3 -0.846200 3 0.0 7.578800 1 0 0.138000 2 -180.0
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Description
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"""""""""""
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The *fourier* dihedral style uses the potential:
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.. math::
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E = \sum_{i=1,m} K_i [ 1.0 + \cos ( n_i \phi - d_i ) ]
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The following coefficients must be defined for each dihedral type via the
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:doc:`dihedral_coeff <dihedral_coeff>` command as in the example above, or in
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the data file or restart files read by the :doc:`read_data <read_data>`
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or :doc:`read_restart <read_restart>` commands:
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* :math:`m` (integer >=1)
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* :math:`K_1` (energy)
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* :math:`n_1` (integer >= 0)
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* :math:`d_1` (degrees)
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* [...]
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* :math:`K_m` (energy)
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* :math:`n_m` (integer >= 0)
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* :math:`d_m` (degrees)
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----------
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.. include:: accel_styles.rst
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----------
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Restrictions
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""""""""""""
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This dihedral style can only be used if LAMMPS was built with the
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EXTRA-MOLECULE package. See the :doc:`Build package <Build_package>` doc
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page for more info.
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Related commands
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""""""""""""""""
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:doc:`dihedral_coeff <dihedral_coeff>`
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Default
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"""""""
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none
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