"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c

:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Commands_all.html)

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pair_style born/coul/dsf/cs command :h3
pair_style born/coul/long/cs command :h3
pair_style born/coul/long/cs/gpu command :h3
pair_style born/coul/wolf/cs command :h3
pair_style born/coul/wolf/cs/gpu command :h3
pair_style buck/coul/long/cs command :h3
pair_style coul/long/cs command :h3
pair_style coul/long/cs/gpu command :h3
pair_style coul/wolf/cs command :h3
pair_style lj/cut/coul/long/cs command :h3

[Syntax:]

pair_style style args :pre

style = {born/coul/dsf/cs} or {born/coul/long/cs} or {born/coul/wolf/cs} or {buck/coul/long/cs} or {coul/long/cs} or {coul/wolf/cs} or {lj/cut/coul/long/cs}
args = list of arguments for a particular style :ul
  {born/coul/dsf/cs} args = alpha cutoff (cutoff2)
    alpha = damping parameter (inverse distance units)
    cutoff = global cutoff for non-Coulombic (and Coulombic if only 1 arg) (distance units)
    cutoff2 = global cutoff for Coulombic (distance units)
  {born/coul/long/cs} args = cutoff (cutoff2)
    cutoff = global cutoff for non-Coulombic (and Coulombic if only 1 arg) (distance units)
    cutoff2 = global cutoff for Coulombic (optional) (distance units)
  {born/coul/wolf/cs} args = alpha cutoff (cutoff2)
    alpha = damping parameter (inverse distance units)
    cutoff = global cutoff for Buckingham (and Coulombic if only 1 arg) (distance units)
    cutoff2 = global cutoff for Coulombic (optional) (distance units)
  {buck/coul/long/cs} args = cutoff (cutoff2)
    cutoff = global cutoff for Buckingham (and Coulombic if only 1 arg) (distance units)
    cutoff2 = global cutoff for Coulombic (optional) (distance units)
  {coul/long} args = cutoff
    cutoff = global cutoff for Coulombic (distance units)
  {coul/wolf} args = alpha cutoff
    alpha = damping parameter (inverse distance units)
    cutoff = global cutoff for Coulombic (distance units)
  {lj/cut/coul/long/cs} args = cutoff (cutoff2)
    cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
    cutoff2 = global cutoff for Coulombic (optional) (distance units) :pre

[Examples:]

pair_style born/coul/dsf/cs 0.1 10.0 12.0
pair_coeff * *   0.0 1.00 0.00 0.00 0.00
pair_coeff 1 1 480.0 0.25 0.00 1.05 0.50 :pre

pair_style born/coul/long/cs 10.0 8.0
pair_coeff 1 1 6.08 0.317 2.340 24.18 11.51 :pre

pair_style born/coul/wolf/cs 0.25 10.0 12.0
pair_coeff * *   0.0 1.00 0.00 0.00 0.00
pair_coeff 1 1 480.0 0.25 0.00 1.05 0.50 :pre

pair_style buck/coul/long/cs 10.0
pair_style buck/coul/long/cs 10.0 8.0
pair_coeff * * 100.0 1.5 200.0
pair_coeff 1 1 100.0 1.5 200.0 9.0 :pre

pair_style coul/long/cs 10.0
pair_coeff * * :pre

pair_style coul/wolf/cs 0.2 9.0
pair_coeff * * :pre

pair_style lj/cut/coul/long/cs 10.0
pair_style lj/cut/coul/long/cs 10.0 8.0
pair_coeff * * 100.0 3.0
pair_coeff 1 1 100.0 3.5 9.0 :pre

[Description:]

These pair styles are designed to be used with the adiabatic
core/shell model of "(Mitchell and Finchham)"_#MitchellFinchham2.  See
the "Howto coreshell"_Howto_coreshell.html doc page for an overview of
the model as implemented in LAMMPS.

All the styles are identical to the corresponding pair style without
the "/cs" in the name:

"pair_style born/coul/dsf"_pair_born.html
"pair_style born/coul/long"_pair_born.html
"pair_style born/coul/wolf"_pair_born.html
"pair_style buck/coul/long"_pair_buck.html
"pair_style coul/long"_pair_coul.html
"pair_style coul/wolf"_pair_coul.html
"pair_style lj/cut/coul/long"_pair_lj.html :ul

except that they correctly treat the special case where the distance
between two charged core and shell atoms in the same core/shell pair
approach r = 0.0.

Styles with a "/long" in the name are used with a long-range solver
for Coulombic interactions via the "kspace_style"_kspace_style.html
command.  They require special treatment of the short-range Coulombic
interactions within the cor/shell model.

Specifically, the short-range Coulomb interaction between a core and
its shell should be turned off using the
"special_bonds"_special_bonds.html command by setting the 1-2 weight
to 0.0, which works because the core and shell atoms are bonded to
each other.  This induces a long-range correction approximation which
fails at small distances (~< 10e-8). Therefore, the Coulomb term which
is used to calculate the correction factor is extended by a minimal
distance (r_min = 1.0-6) when the interaction between a core/shell
pair is treated, as follows

:c,image(Eqs/pair_cs.jpg)

where C is an energy-conversion constant, Qi and Qj are the charges on
the core and shell, epsilon is the dielectric constant and r_min is the
minimal distance.

For styles that are not used with a long-range solver, i.e. those with
"/dsf" or "/wolf" in the name, the only correction is the addition of
a minimal distance to avoid the possible r = 0.0 case for a core/shell
pair.

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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 on the "Speed packages"_Speed_packages.html doc
page.  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 "Build
package"_Build_package.html doc page 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"_Run_options.html when you invoke LAMMPS, or you can use the
"suffix"_suffix.html command in your input script.

See the "Speed packages"_Speed_packages.html doc page for more
instructions on how to use the accelerated styles effectively.

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[Mixing, shift, table, tail correction, restart, rRESPA info]:

See the corresponding doc pages for pair styles without the "cs"
suffix to see how mixing, shifting, tabulation, tail correction,
restarting, and rRESPA are handled by theses pair styles.

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[Restrictions:]

These pair styles are part of the CORESHELL package.  They are only
enabled if LAMMPS was built with that package.  See the "Build
package"_Build_package.html doc page for more info.

[Related commands:]

"pair_coeff"_pair_coeff.html, "pair_style born"_pair_born.html,
"pair_style buck"_pair_buck.html

[Default:] none

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:link(MitchellFinchham2)
[(Mitchell and Finchham)] Mitchell, Finchham, J Phys Condensed Matter,
5, 1031-1038 (1993).
