PositionRestraint #

It restrains a particle to a fixed point in a space via harmonic potential.

Example #

[[forcefields.external]]
interaction = "PositionRestraint"
potential   = "Harmonic"
parameters  = [
    {index = 0, position = [0.0, 0.0, 0.0], k = 0.1, v0 = 10.0},
    # ...
]

Input Reference #

• interaction: String
  • Name of the interaciton. Here, it is "PositionRestraint".
• potential: String
  • Name of the potential. Currently, only the harmonic potential is available.
• parameters: Table
  • index: Integer
    • The index of the particle. The index is 0-based.
  • offset: Integer (Optional. By default, 0.)
    • The offset value for the index.
  • position: Array of Floatings
    • The cartesian coordinate (x, y, and z in this order) of the position.
  • k: Floating
    • The strength of the restraint.
  • v0: Floating
    • The native distance from the point.
    • To restrain a particle exactly at the position, set 0.