lammps/doc/bond_fene.txt

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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)
:line
bond_style fene command :h3
[Syntax:]
bond_style fene :pre
[Examples:]
bond_style fene
bond_coeff 1 30.0 1.5 1.0 1.0 :pre
[Description:]
The {fene} bond style uses the potential
:c,image(Eqs/bond_fene.jpg)
to define a finite extensible nonlinear elastic (FENE) potential
"(Kremer)"_#Kremer, used for bead-spring polymer models. The first
term is attractive, the 2nd Lennard-Jones term is repulsive. The
first term extends to R0, the maximum extent of the bond. The 2nd
term is cutoff at 2^(1/6) sigma, the minimum of the LJ potential.
The following coefficients must be defined for each bond type via the
"bond_coeff"_bond_coeff.html command as in the example above, or in
the data file or restart files read by the "read_data"_read_data.html
or "read_restart"_read_restart.html commands:
K (energy/distance^2)
R0 (distance)
epsilon (energy)
sigma (distance) :ul
[Restrictions:]
This bond style can only be used if LAMMPS was built with the
"molecular" package (which it is by default). See the "Making
LAMMPS"_Section_start.html#2_3 section for more info on packages.
You typically should specify "special_bonds 0 1 1"_special_bonds.html
to use this bond style. LAMMPS will issue a warning it that's not the
case.
[Related commands:]
"bond_coeff"_bond_coeff.html, "delete_bonds"_delete_bonds.html
[Default:] none
:line
:link(Kremer)
[(Kremer)] Kremer, Grest, J Chem Phys, 92, 5057 (1990).