Homec4science
Diffusion lammps (master) Browse

lammps/doc/html/_sources/bond_morse.txt
32ba20085de8master

Last Change
Raw File

bond_morse.txt
View Options

.. index:: bond_style morse
bond_style morse command
========================
bond_style morse/omp command
============================
Syntax
""""""
.. parsed-literal::
bond_style morse
Examples
""""""""
.. parsed-literal::
bond_style morse
bond_coeff 5 1.0 2.0 1.2
Description
"""""""""""
The *morse* bond style uses the potential
.. image:: Eqs/bond_morse.jpg
:align: center
where r0 is the equilibrium bond distance, alpha is a stiffness
parameter, and D determines the depth of the potential well.
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:
* D (energy)
* alpha (inverse distance)
* r0 (distance)
----------
Styles with a *gpu*\ , *intel*\ , *kk*\ , *omp*\ , or *opt* suffix are
functionally the same as the corresponding style without the suffix.
They have been optimized to run faster, depending on your available
hardware, as discussed in :doc:`Section_accelerate <Section_accelerate>`
of the manual. The accelerated styles take the same arguments and
should produce the same results, except for round-off and precision
issues.
These accelerated styles are part of the GPU, USER-INTEL, KOKKOS,
USER-OMP and OPT packages, respectively. They are only enabled if
LAMMPS was built with those packages. See the :ref:`Making LAMMPS <start_3>` section for more info.
You can specify the accelerated styles explicitly in your input script
by including their suffix, or you can use the :ref:`-suffix command-line switch <start_7>` when you invoke LAMMPS, or you can
use the :doc:`suffix <suffix>` command in your input script.
See :doc:`Section_accelerate <Section_accelerate>` of the manual for
more instructions on how to use the accelerated styles effectively.
----------
Restrictions
""""""""""""
This bond style can only be used if LAMMPS was built with the
MOLECULE package (which it is by default). See the :ref:`Making LAMMPS <start_3>` section for more info on packages.
Related commands
""""""""""""""""
:doc:`bond_coeff <bond_coeff>`, :doc:`delete_bonds <delete_bonds>`
**Default:** none
.. _lws: http://lammps.sandia.gov
.. _ld: Manual.html
.. _lc: Section_commands.html#comm
c4science · Help