Size and Shape of the Polyelectrolyte

We now consider the effect of salt concentration on a. In the simulation, first a salt-free solution of polyelectrolyte chains and their monovalent counterions are equilibrated. For specifidty, we denote the counterion as X, and there are N counterions (Zc = 1), and take the polymer to be uniformly negatively charged. Next, we add a fixed quantity of salt of either the type XY (Z+ = 1 = Z ) or the type AYz (Z + =2, Z = 1) to the system and again equilibrate the system. We then collect the statistics and compute the average number of various ions (X, Y, and A) in the counterion worm surrounding the polymer defined as above with = 2lo. We illustrate the key results only for the case of N = 100 and Cp = 8 x lO l  

We will later notice that theory predicts overcharging in the presence of dielectric inhomogoneity of the solvent This variation of the dielectric constant is not addressed in present simulations. 

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