Bordi F, Cametti C, Sennato S, Zuzzi S, Dou S, Colby R H
Dipartimento di Fisica, Universita' di Roma La Sapienza, Piazzale A. Moro 5, I-00185, Rome, Italy.
Phys Chem Chem Phys. 2006 Aug 21;8(31):3653-8. doi: 10.1039/b605624e. Epub 2006 Jul 3.
In this note, we present a set of radiowave dielectric spectroscopy measurements of two dilute, differently-charged polyelectrolyte solutions, under different solvent conditions. We have found that both the dielectric strength, Delta epsilon, and the relaxation time, tau(ion), of the dielectric relaxation process associated with the counterion polarization along a length scale of the order of the correlation length obey the scaling laws with the polyion concentration, according to the Ito model. This is verified with good accuracy independently of the quality of the solvent, which has been varied from poor to good solvent conditions. This finding supports evidence to the fact that, in dilute solutions, the counterion polarization is independent of the polyion concentration, in spite of what occurs at the semi-dilute concentrations.
在本笔记中,我们展示了在不同溶剂条件下对两种稀释的、带不同电荷的聚电解质溶液进行的一组无线电波介电谱测量。我们发现,根据伊藤模型,与反离子极化相关的介电弛豫过程的介电强度Δε和弛豫时间τ(离子),在与相关长度量级相当的长度尺度上,均遵循与聚离子浓度的标度律。这一结果在从不良溶剂到良溶剂条件变化的情况下,均得到了高精度的验证,且与溶剂质量无关。这一发现为以下事实提供了证据:在稀溶液中,尽管在半稀溶液中会出现不同情况,但反离子极化与聚离子浓度无关。