Department of Chemistry, Purdue University, West Lafayette, Indiana, USA.
Faraday Discuss. 2013;160:255-70; discussion 311-27. doi: 10.1039/c2fd20082a.
Interactions between halide ions (fluoride and iodide) and t-butyl alcohol (TBA) dissolved in water are probed using a recently developed hydration-shell spectroscopic technique and theoretical cluster and liquid calculations. High ignal-to-noise Raman spectroscopic measurements are combined with multivariate curve resolution (Raman-MCR) to reveal that while there is little interaction between aqueous fluoride ions and TBA, iodide ions break down the tetrahedral hydration-shell structure of TBA and produce a red-shift in its CH stretch frequency, in good agreement with the theoretical effective fragment potential (EFP) molecular dynamics simulations and hybrid quantum/EFP frequency calculations. The results imply that there is a significantly larger probability of finding iodide than fluoride in the first hydration shell of TBA, although the local iodide concentration is apparently not as high as in the surrounding bulk aqueous NaI solution.
使用最近开发的水合壳光谱技术以及理论簇和液体计算，研究了卤化物离子（氟化物和碘化物）与溶解在水中的叔丁醇（TBA）之间的相互作用。高信噪比拉曼光谱测量与多元曲线分辨（Raman-MCR）相结合，揭示出水溶液中的氟离子与 TBA 之间几乎没有相互作用，而碘离子破坏了 TBA 的四面体水合壳结构，并使其 CH 伸缩频率发生红移，这与理论有效片段势能（EFP）分子动力学模拟和混合量子/EFP 频率计算结果一致。结果表明，尽管 TBA 第一水合壳层中的局部碘离子浓度显然不如周围的 NaI 水溶液高，但在 TBA 的第一水合壳层中找到碘化物的可能性明显大于找到氟化物的可能性。
