66 lines
1.2 KiB
ReStructuredText
66 lines
1.2 KiB
ReStructuredText
.. index:: dihedral_style nharmonic
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.. index:: dihedral_style nharmonic/omp
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dihedral_style nharmonic command
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================================
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Accelerator Variants: *nharmonic/omp*
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Syntax
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""""""
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.. code-block:: LAMMPS
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dihedral_style nharmonic
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Examples
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""""""""
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.. code-block:: LAMMPS
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dihedral_style nharmonic
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dihedral_coeff * 3 10.0 20.0 30.0
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Description
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"""""""""""
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The *nharmonic* dihedral style uses the potential:
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.. math::
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E = \sum_{n=1,n} A_n \cos^{n-1}(\phi)
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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:`n` (integer >=1)
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* :math:`A_1` (energy)
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* :math:`A_2` (energy)
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* ...
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* :math:`A_n` (energy)
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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 angle style can only be used if LAMMPS was built with the
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USER_MISC 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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