Size of a polyelectrolyte chain in solution containing counterions

Using the method of Edwards and Singh we calculate the mean square radius 〈R2〉 of the polyelectrolyte chain in solution containing counterions for the temperature greater than the Flory’s θ temperature. For the counterion density n we obtain: (a) 〈R2〉∝L2 when n→0, and (b) 〈R2〉∝L6/5 when n→∞. These results are in agreement with the Flory-type calculations and recent Monte Carlo simulations performed by Baumgärtner.