Solvatochromism: a dielectric continuum model applied to supercritical fluids
Solvatochromism: a dielectric continuum model applied to supercritical fluids
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溶剂变色现象：应用于超临界流体的介电连续介质模型
DOI：
10.1021/j100312a050
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Richard D. Smith
中科院分区：
文献类型：
--
作者：
C. Yonker;Richard D. Smith
根据 ..pi..* Kamlet 和 Taft 极性/极化率参数，将非极性超临界流体的溶剂化变色行为与 McRae-Bayliss 模型进行比较。对于在低反应场值（低密度）下研究的流体，可以看到 ..pi..* 相对于 Onsager 反应场 (F/sub 0/) 的绘图出现中断。 ..pi..* 和 Onsager 反应场 (F/sub 0/) 之间的关系显示出两个几乎线性行为的区域。从低密度区域到高密度区域的转变，其中观察到 ..pi..* 对 (F/sub 0/) 的依赖性较小，暂时归因于溶质周围广泛的溶剂聚集。这一假设得到了先前观察到的流体中溶质的部分摩尔体积 anti v/sub 2/无穷大作为压力函数的行为的支持。抗 v/sub 2/无穷大的快速变化也显示发生在流体的溶剂化变色行为发生变化并且溶质的溶解度急剧增加的同一区域。
The solvatochromic behavior of nonpolar supercritical fluids, in terms of the ..pi..* Kamlet and Taft polarity/polarizability parameter, is compared to the McRae-Bayliss model. A break in the plot of ..pi..* against the Onsager reaction field (F/sub 0/) is seen for the fluids studied at low reaction field values (low densities). The relationship between ..pi..* and the Onsager reaction field (F/sub 0/) shows two regions of nearly linear behavior. The transition from the low-density region to higher density region, where a smaller dependence of ..pi..* upon (F/sub 0/) is observed, is tentatively attributed to extensive solvent clustering about the solute. This hypothesis is supported by the behavior previously observed for the partial molar volume of the solute in the fluid anti v/sub 2/ infinity as a function of pressure. The rapid change in anti v/sub 2/ infinity is also shown to occur in the same region where the solvatochromic behavior of the fluid changes and the solute's solubility increases dramatically.