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Comment on ``Adsorption of Polyelectrolyte onto a Colloid of Opposite Charge''

Ramin Golestanian
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Abstract

In a recent Letter, Gurovitch and Sens studied the adsorption of a weakly charged polyelectrolyte chain onto an oppositely charged colloidal particle. By using a variational technique they found that the colloidal particle can adsorb a polymer of higher charge than its own, and thus be ``overcharged.'' I argue that the observed overcharging by a factor of 16/5 is indeed an artifact of the approximations involved in the study. Moreover, I show that the existence of overcharging depends crucially on the choice of the trial wave function, contrary to their claim.

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Ramin Golestanian. 1999-09-17. Comment on ``Adsorption of Polyelectrolyte onto a Colloid of Opposite Charge''. https://doi.org/10.1103/physrevlett.83.2473

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