"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

angle_style cosine/delta command :h3

[Syntax:]

angle_style cosine/delta :pre

[Examples:]

angle_style cosine/delta
angle_coeff 2*4 75.0 100.0 :pre

[Description:]

The {cosine/delta} angle style uses the potential

:c,image(Eqs/angle_cosine_delta.jpg)

where theta0 is the equilibrium value of the angle, and K is a
prefactor.  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, or in
the data file or restart files read by the "read_data"_read_data.html
or "read_restart"_read_restart.html commands:

K (energy)
theta0 (degrees) :ul

Theta0 is specified in degrees, but LAMMPS converts it to radians
internally.

[Restrictions:]

This angle 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.

[Related commands:]

"angle_coeff"_angle_coeff.html, "angle_style
cosine/squared"_angle_cosine_squared.html

[Default:] none
