Conformational properties of weakly charged polyelectrolytes from Monte Carlo simulations

Abstract

Abstract We present results of off‐lattice Monte Carlo simulations of weakly charged chains where the charged beads interact with a screened Coulomb potential of Debye‐Hückel type. The behaviour of the mean square end‐to‐end distance and mean‐square radius of gyration versus chain length is discussed for various solution conditions characterized by the parameter ζ = 2λ D / b , with λ D being the Debye screening length and b the contour distance between neighbouring charged beads. We also evaluate the probability‐density distribution for the end‐to‐end distance R . From the angular correlation function 〈cos γ k 〉 we estimate the persistence length as well as the chain length dependence of 〈 R 2 〉 and 〈 R G 2 〉. With increasing ζ it is found to come close to that which is directly obtained from 〈 R 2 ( N )〈 and 〈 R G 2 ( N )〉. Furthermore, the nonexponential decay of correlations indicates our charged chains to be not wormlike.