The charged particles furthermore interact through the standard Coulomb potential. The relative permittivity of the background corresponds to water at room temperature with a dielectric constant ε r = 78. This results in the Bjerrum length l B = e 2 /ε r k B T = 0.7 nm at T = 298 K, where e is the elementary charge and k B is the Boltzmann constant. The bonds between adjacent monomers in the polymer chain are modeled with a harmonic potential with a spring constant k = 100 k B T nm -2 and a bond length b = 0.38 nm. Neither angular, nor torsional potential is applied. Non-bonded interactions between adjacent monomers are excluded.