67 lines
1.3 KiB
ReStructuredText
67 lines
1.3 KiB
ReStructuredText
.. index:: bond_style morse
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.. index:: bond_style morse/omp
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bond_style morse command
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========================
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Accelerator Variants: *morse/omp*
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Syntax
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""""""
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.. code-block:: LAMMPS
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bond_style morse
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Examples
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""""""""
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.. code-block:: LAMMPS
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bond_style morse
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bond_coeff 5 1.0 2.0 1.2
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Description
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"""""""""""
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The *morse* bond style uses the potential
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.. math::
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E = D \left[ 1 - e^{-\alpha (r - r_0)} \right]^2
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where :math:`r_0` is the equilibrium bond distance, :math:`\alpha` is a stiffness
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parameter, and :math:`D` determines the depth of the potential well.
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The following coefficients must be defined for each bond type via the
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:doc:`bond_coeff <bond_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:`D` (energy)
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* :math:`\alpha` (inverse distance)
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* :math:`r_0` (distance)
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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 bond style can only be used if LAMMPS was built with the MOLECULE
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package. See the :doc:`Build package <Build_package>` page for more
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info.
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Related commands
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""""""""""""""""
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:doc:`bond_coeff <bond_coeff>`, :doc:`delete_bonds <delete_bonds>`
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Default
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"""""""
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none
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