.. index:: bond_style harmonic

bond_style harmonic command
===========================

Syntax
""""""

.. parsed-literal::

   bond_style harmonic

Examples
""""""""

.. parsed-literal::

   bond_style harmonic
   bond_coeff 5 80.0 1.2

Description
"""""""""""

The *harmonic* bond style uses the potential

.. image:: Eqs/bond_harmonic.jpg
   :align: center

where r0 is the equilibrium bond distance.  Note that the usual 1/2
factor is included in K.

The following coefficients must be defined for each bond type via the
:doc:`bond_coeff <bond_coeff>` command as in the example above, or in
the data file or restart files read by the :doc:`read_data <read_data>`
or :doc:`read_restart <read_restart>` commands:

* K (energy/distance^2)
* r0 (distance)

Restrictions
""""""""""""


This bond style can only be used if LIGGGHTS(R)-PUBLIC was built with the
MOLECULAR package (which it is by default).  See the :ref:`Making LIGGGHTS(R)-PUBLIC <start_3>` section for more info on packages.

Related commands
""""""""""""""""

:doc:`bond_coeff <bond_coeff>`, :doc:`delete_bonds <delete_bonds>`

**Default:** none


.. _liws: http://www.cfdem.com
.. _ld: Manual.html
.. _lc: Section_commands.html#comm