Salt-induced collapse and reexpansion of highly charged flexible polyelectrolytes
Salt-induced collapse and reexpansion of highly charged flexible polyelectrolytes
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DOI：
10.1103/physrevlett.97.148301
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发表时间：
2006-10-06
影响因子：
8.6
通讯作者：
Luijten, Erik
中科院分区：
文献类型：
--
作者：
Hsiao, Pai-Yi;Luijten, Erik
通过计算机模拟研究了稀柔性聚电解质在溶液中的盐依赖性构象。低浓度的多价盐会引起已知的单个多电解质链的构象崩溃，但随着盐浓度的进一步增加，随后会发生再膨胀。我们明确地证明了多价反离子可以在再膨胀机制中过度补偿链的裸电荷。再膨胀的程度和过充电的发生都敏感地取决于离子的大小。我们的发现与广泛的盐诱导络合现象相关。
We study the salt-dependent conformations of dilute flexible polyelectrolytes in solution via computer simulations. Low concentrations of multivalent salt induce the known conformational collapse of individual polyelectrolyte chains, but as the salt concentration is increased further this is followed by a reexpansion. We explicitly demonstrate that multivalent counterions can overcompensate the bare charge of the chain in the reexpansion regime. Both the degree of reexpansion and the occurrence of overcharging sensitively depend on ion size. Our findings are relevant for a wide range of salt-induced complexation phenomena.