lammps/doc/bond_hybrid.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 hybrid command :h3
[Syntax:]
bond_style hybrid style1 style2 ... :pre
style1,style2 = list of one or more bond styles :ul
[Examples:]
bond_style hybrid harmonic fene
bond_coeff 1 harmonic 80.0 1.2
bond_coeff 2* fene 30.0 1.5 1.0 1.0 :pre
[Description:]
The {hybrid} style enables the use of multiple bond styles in one
simulation. A bond style is assigned to each bond type. For example,
bonds in a polymer flow (of bond type 1) could be computed with a
{fene} potential and bonds in the wall boundary (of bond type 2) could
be computed with a {harmonic} potential. The assignment of bond type
to style is made via the "bond_coeff"_bond_coeff.html command or in
the data file.
In the bond_coeff command, the first coefficient sets the bond style
and the remaining coefficients are those appropriate to that style.
In the example above, the 2 bond_coeff commands would set bonds of
bond type 1 to be computed with a {harmonic} potential with
coefficients 80.0, 1.2 for K, r0. All other bond types (2-N) would be
computed with a {fene} potential with coefficients 30.0, 1.5, 1.0, 1.0
for K, R0, epsilon, sigma.
A bond style of {none} can be specified as the 2nd argument to the
bond_coeff command, if you desire to turn off certain bond types.
[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.
Unlike other bond styles, the hybrid bond style does not store bond
coefficient info for individual sub-styles in a "binary restart
files"_restart.html. Thus when retarting a simulation from a restart
file, you need to re-specify bond_coeff commands.
[Related commands:]
"bond_coeff"_bond_coeff.html, "delete_bonds"_delete_bonds.html
[Default:] none