\(\renewcommand{\AA}{\text{Å}}\)
angle_style mwlc command
Syntax
angle_style mwlc
Examples
angle_style mwlc
angle_coeff * 25 1 10 1
Description
Added in version 4Feb2025.
The mwlc angle style models a meltable wormlike chain and can be used to model non-linear bending elasticity of polymers, e.g. DNA. mwlc uses a potential that is a canonical-ensemble superposition of a non-melted and a melted state (Farrell). The potential is
where the non-melted and melted partition functions are
\(k_1\) is the bending elastic constant of the non-melted state, \(k_2\) is the bending elastic constant of the melted state, \(\mu\) is the melting energy, and \(T\) is the reference temperature. The reference energy,
ensures that E is zero for a fully extended chain.
This potential is a continuous version of the two-state potential introduced by (Yan).
The following coefficients must be defined for each angle type via the angle_coeff command as in the example above, or in the data file or restart files read by the read_data or read_restart commands:
\(k_1\) (energy)
\(k_2\) (energy)
\(\mu\) (energy)
\(T\) (temperature)
Restrictions
This angle style can only be used if LAMMPS was built with the EXTRA-MOLECULE package. See the Build package doc page for more info.
Default
none
(Farrell) Farrell, Dobnikar, Podgornik, Curk, Phys Rev Lett, 133, 148101 (2024).