Fluctuations and interactions of semi-flexible polyelectrolytes in columnar assemblies.
Fluctuations and interactions of semi-flexible polyelectrolytes in columnar assemblies.
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柱状组件中半柔性聚电解质的波动和相互作用。
DOI：
10.1088/0953-8984/22/7/072202
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Wynveen,A
中科院分区：
文献类型：
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作者：
Lee,DJ;Leikin,S;Wynveen,A
我们已经开发了半柔性聚电解质的柱状聚集体的统计理论。以前的简化理论的适用性仅限于具有不切实际的高有效电荷的聚电解质，因此具有强烈抑制的热波动。为了避免这个问题，我们利用更一致的近似短程图像电荷力和空间限制，从而在新的预测聚电解质更实际的重要性，较低的有效线性电荷密度。在本文中，我们专注于具有均匀表面电荷密度的蠕虫状链的聚集体，尽管相同的基本思想也可以应用于结构化聚电解质。我们发现，波动有效地扩大聚电解质之间的静电相互作用的范围后，减少聚集体密度，定性与以前的理论。然而，与以前的理论相比，我们证明，空间限制提供了主导的，而不是一个可以忽略不计的贡献，在较高的聚集体密度和显着的定量校正，在较低的密度，导致渗透压等温线，大大不同于以前的预测。
We have developed a statistical theory for columnar aggregates of semi-flexible polyelectrolytes. The applicability of previous, simplified theories was limited to polyelectrolytes with unrealistically high effective charge and, hence, with strongly suppressed thermal undulations. To avoid this problem, we utilized more consistent approximations for short-range image–charge forces and steric confinement, resulting in new predictions for polyelectrolytes with more practically important, lower effective linear charge densities. In the present paper, we focus on aggregates of wormlike chains with uniform surface charge density, although the same basic ideas may also be applied to structured polyelectrolytes. We find that undulations effectively extend the range of electrostatic interactions between polyelectrolytes upon decreasing aggregate density, in qualitative agreement with previous theories. However, in contrast to previous theories, we demonstrate that steric confinement provides the dominant rather than a negligible contribution at higher aggregate densities and significant quantitative corrections at lower densities, resulting in osmotic pressure isotherms that drastically differ from previous predictions.