Divalent Salt and Overcharging

Chain Contraction Contrasting Effects of Mono and Divalent Salts 

This continuous shrinkage of a generic polyelectrolyte (NaPSS) chain in water occurs for modest values of 6, at a modest presence of the divalent salt, and at room temperature. This phenomenon has been noticed theoretically [6] and in experiments [34—37] and simulations [27, 33]. 

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