lammps/doc/bond_class2.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)
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bond_style class2 command :h3
bond_style class2/omp command :h3
[Syntax:]
bond_style class2 :pre
[Examples:]
bond_style class2
bond_coeff 1 1.0 100.0 80.0 80.0 :pre
[Description:]
The {class2} bond style uses the potential
:c,image(Eqs/bond_class2.jpg)
where r0 is the equilibrium bond distance.
See "(Sun)"_#Sun for a description of the COMPASS class2 force field.
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:
R0 (distance)
K2 (energy/distance^2)
K3 (energy/distance^3)
K4 (energy/distance^4) :ul
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Styles with a {cuda}, {gpu}, {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 "Section_accelerate"_Section_accelerate.html 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 USER-CUDA, GPU, USER-OMP and OPT
packages, respectively. They are only enabled if LAMMPS was built with
those packages. See the "Making LAMMPS"_Section_start.html#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 "-suffix command-line
switch"_Section_start.html#start_7 when you invoke LAMMPS, or you can
use the "suffix"_suffix.html command in your input script.
See "Section_accelerate"_Section_accelerate.html of the manual for
more instructions on how to use the accelerated styles effectively.
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[Restrictions:]
This bond style can only be used if LAMMPS was built with the CLASS2
package. See the "Making LAMMPS"_Section_start.html#start_3 section
for more info on packages.
[Related commands:]
"bond_coeff"_bond_coeff.html, "delete_bonds"_delete_bonds.html
[Default:] none
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:link(Sun)
[(Sun)] Sun, J Phys Chem B 102, 7338-7364 (1998).