WormLikeChainOffset

WormLikeChainOffset #

A potential function based on the Worm-Like chain model with distance offset.

\[U(r) = \begin{cases} 0 & ( r < l_0 ) \\ \frac{k_B T}{p} \left(\frac{l_c}{4} \left[ \frac{1}{1 - \frac{r - l_0}{l_c}} - 1 \right] - \frac{r - l_0}{4} + \frac{\left(r - l_0 \right)^2}{2l_c}\right) & ( r \geq l_0 ) \\ \end{cases}\]

Example #

[[forcefields.local]]
interaction = "BondLength"
potential   = "WormLikeChainOffset"
topology    = "bond"
parameters  = [
    {indices = [0, 1], offset = 100, p = 5.0, lc = 100.0, l0 = 30.0},
    # ...
]

Input Reference #

  • p: Floating
    • The persistent length of the polymer.
  • lc: Floating
    • The maximum length of the polymer.
  • l0: Floating
    • The offset length of the distance between two particles.
  • indices: Array of Integers (length = 2)
    • Indices of particles that interact with each other. The index is 0-based.
  • offset: Integer(Optional. By default, 0.)
    • Offset of index.

Remarks #

This feature is developed by contributor, @yutakasi634.