lammps/doc/pair_beck.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
pair_style beck command :h3
pair_style beck/omp command :h3
[Syntax:]
pair_style beck Rc :pre
Rc = cutoff for interactions (distance units) :ul
[Examples:]
pair_style beck 8.0
pair_coeff * * 399.671876712 0.0000867636112694 0.675 4.390 0.0003746
pair_coeff 1 1 399.671876712 0.0000867636112694 0.675 4.390 0.0003746 6.0 :pre
[Description:]
Style {beck} computes interactions based on the potential by
"(Beck)"_#Beck, originally designed for simulation of Helium. It
includes truncation at a cutoff distance Rc.
:c,image(Eqs/pair_beck.jpg)
The following coefficients must be defined for each pair of atoms
types via the "pair_coeff"_pair_coeff.html command as in the examples
above, or in the data file or restart files read by the
"read_data"_read_data.html or "read_restart"_read_restart.html
commands.
A (energy units)
B (energy-distance^6 units)
a (distance units)
alpha (1/distance units)
beta (1/distance^6 units)
cutoff (distance units) :ul
The last coefficient is optional. If not specified, the global cutoff
Rc is used.
:line
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.
:line
[Mixing, shift, table, tail correction, restart, rRESPA info]:
For atom type pairs I,J and I != J, coeffiecients must be specified.
No default miture rules are used.
This pair style does not support the "pair_modify"_pair_modify.html shift
option for the energy of the pair interaction.
The "pair_modify"_pair_modify.html table option is not relevant
for this pair style.
This pair style does not support the "pair_modify"_pair_modify.html
tail option for adding long-range tail corrections.
This pair style writes its information to "binary restart
files"_restart.html, so pair_style and pair_coeff commands do not need
to be specified in an input script that reads a restart file.
This pair style can only be used via the {pair} keyword of the
"run_style respa"_run_style.html command. It does not support the
{inner}, {middle}, {outer} keywords.
:line
[Restrictions:] none
[Related commands:]
"pair_coeff"_pair_coeff.html
[Default:] none
:line
:link(Beck)
[(Beck)] Beck, Molecular Physics, 14, 311 (1968).