Syntax:
improper_style harmonic
Examples:
improper_style harmonic improper_coeff 1 100.0 0
Description:
The harmonic improper style uses the potential
where X is the improper angle, X0 is its equilibrium value, and K is a prefactor. Note that the usual 1/2 factor is included in K.
The following coefficients must be defined for each improper type via the improper_coeff command as in the example above, or in the data file or restart files read by the read_data or read_restart commands:
X0 is specified in degrees, but LAMMPS converts it to radians internally; hence the units of K are in energy/radian^2.
Restrictions:
Improper styles can only be set for atom styles that allow impropers to be defined.
This improper style is part of the "molecular" package. It is only enabled if LAMMPS was built with that package. See the Making LAMMPS section for more info.
Related commands:
Default: none