Large-scale supramolecular structure in solutions of low molar mass compounds and mixtures of liquids: I. Light scattering characterization.
Large-scale supramolecular structure in solutions of low molar mass compounds and mixtures of liquids: I. Light scattering characterization.
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DOI：
10.1021/jp0569335
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发表时间：
2006-02
期刊：
影响因子：
--
通讯作者：
M. Sedlák
中科院分区：
文献类型：
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作者：
M. Sedlák
静态和动态激光光散射被用来带来的证据大规模的超分子结构的低摩尔质量的电解质，非电解质，和液体的混合物的解决方案。结果表明，溶质在大尺度上分布不均匀。溶液中存在较高和较低溶质浓度的区域，并为实验观察提供足够的散射对比度。一个详细的光散射研究表明，这些地区的特点是接近球形的离散域较高的溶质密度在一个较低密度的解决方案。这些结构域内部确实含有溶剂，因此可以表征为松散的缔合物（巨簇，聚集体）。它们的尺寸分布非常广泛，范围高达数百纳米。因此，这些不均匀性的特征尺寸超过单个分子的埃尺寸几个数量级。每个畴的溶质分子数大约在10（3）-10（8）的范围内变化。所描述的现象在非常宽范围的溶质和溶剂中观察到。除其他外，还介绍了具有重要化学和生物学意义的最常见物质的选定数据，如氯化钠、柠檬酸、葡萄糖、尿素、乙酸和乙醇。
Static and dynamic laser light scattering were used to bring evidence of large-scale supramolecular structure in solutions of low molar mass electrolytes, nonelectrolytes, and mixtures of liquids. It was shown that solutes are distributed inhomogeneously on large length scales. Regions of higher and lower solute concentration exist in solution and give sufficient scattering contrast for experimental observation. A detailed light scattering study showed that these regions can be characterized as close-to-spherical discrete domains of higher solute density in a less dense rest of solution. These domains do contain solvent inside and can be therefore characterized as loose associates (giant clusters, aggregates). Their size distributions are significantly broad, ranging up to several hundreds of nanometers. Characteristic sizes of these inhomogenities thus exceed angstrom dimensions of individual molecules by several orders of magnitude. The number of solute molecules per domain varies approximately in the range 10(3)-10(8). Phenomena described were observed in a very broad range of solutes and solvents. Among others, selected data on most common substances of great chemical and biological importance such as sodium chloride, citric acid, glucose, urea, acetic acid, and ethanol are presented.