69 lines
1.3 KiB
ReStructuredText
69 lines
1.3 KiB
ReStructuredText
.. index:: bond_style harmonic
|
|
|
|
bond_style harmonic command
|
|
===========================
|
|
|
|
bond_style harmonic/intel command
|
|
=================================
|
|
|
|
bond_style harmonic/kk command
|
|
==============================
|
|
|
|
bond_style harmonic/omp command
|
|
===============================
|
|
|
|
Syntax
|
|
""""""
|
|
|
|
.. code-block:: LAMMPS
|
|
|
|
bond_style harmonic
|
|
|
|
Examples
|
|
""""""""
|
|
|
|
.. code-block:: LAMMPS
|
|
|
|
bond_style harmonic
|
|
bond_coeff 5 80.0 1.2
|
|
|
|
Description
|
|
"""""""""""
|
|
|
|
The *harmonic* bond style uses the potential
|
|
|
|
.. math::
|
|
|
|
E = K (r - r_0)^2
|
|
|
|
where :math:`r_0` is the equilibrium bond distance. Note that the usual 1/2
|
|
factor is included in :math:`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:
|
|
|
|
* :math:`K` (energy/distance\^2)
|
|
* :math:`r_0` (distance)
|
|
|
|
----------
|
|
|
|
.. include:: accel_styles.rst
|
|
|
|
----------
|
|
|
|
Restrictions
|
|
""""""""""""
|
|
|
|
This bond style can only be used if LAMMPS was built with the MOLECULE
|
|
package. See the :doc:`Build package <Build_package>` doc page for more
|
|
info.
|
|
|
|
Related commands
|
|
""""""""""""""""
|
|
|
|
:doc:`bond_coeff <bond_coeff>`, :doc:`delete_bonds <delete_bonds>`
|
|
|
|
**Default:** none
|