"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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angle_style sdk command :h3
angle_style sdk/omp command :h3

[Syntax:]

angle_style sdk :pre
angle_style sdk/omp :pre

[Examples:]

angle_style sdk
angle_coeff 1 300.0 107.0 :pre

[Description:]

The {sdk} angle style is a combination of the harmonic angle potential,

:c,image(Eqs/angle_harmonic.jpg)

where theta0 is the equilibrium value of the angle and K a prefactor,
with the {repulsive} part of the non-bonded {lj/sdk} pair style
between the atoms 1 and 3.  This angle potential is intended for
coarse grained MD simulations with the CMM parameterization using the
"pair_style lj/sdk"_pair_sdk.html.  Relative to the pair_style
{lj/sdk}, however, the energy is shifted by {epsilon}, to avoid sudden
jumps.  Note that the usual 1/2 factor is included in K.

The following coefficients must be defined for each angle type via the
"angle_coeff"_angle_coeff.html command as in the example above:

K (energy/radian^2)
theta0 (degrees) :ul

Theta0 is specified in degrees, but LAMMPS converts it to radians
internally; hence the units of K are in energy/radian^2.
The also required {lj/sdk} parameters will be extracted automatically
from the pair_style.

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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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[Restrictions:]

This angle style can only be used if LAMMPS was built with the
USER-CGSDK package.  See the "Build package"_Build_package.html doc
page for more info.

[Related commands:]

"angle_coeff"_angle_coeff.html, "angle_style
harmonic"_angle_harmonic.html, "pair_style lj/sdk"_pair_sdk.html,
"pair_style lj/sdk/coul/long"_pair_sdk.html

[Default:] none
