Solvatochromic Studies of Solvated Surface Phases

这笔赠款是在分析和表面化学的一般领域，以及分离科学的子领域。萨拉·鲁坦教授将研究用于液体色谱的固定相的结构。通过在特定的溶剂环境中使用分子探针的光学光谱的组合，她将确定系统的所谓的溶剂变色参数。通过这种方法，可以确定液固界面上分子物种的基本结构和反应活性。对导致流动中分子物种分离的分子相互作用的机制将有更好的理解。将确定探针分子与高效液相色谱固定相之间的分子相互作用。将测量和分析光学(UV-可见光和红外)光谱频移，以消除溶液相干扰。偶极性--极化率、氢键酸度和碱度将使我们能够了解基于溶剂的反应性和在分离和其他液-固界面系统中的吸附效应。特殊的溶剂系统将包括甲醇、乙腈和四氢呋喃-水的混合物，这些混合物通常用于高效液相色谱。将研究碳氢化合物和苯基改性白炭黑以及未改性白炭黑。探针分子包括一系列通常用于探测溶剂溶质相互作用的硝基苯胺染料。独特的执行多组分分析和消除液相影响的能力将有助于提高目前对溶液中分子水平上的吸附动力学的理解水平。

This grant is in the general field of analytical and surface chemistry and in the subfield of separations science. Professor Sarah Rutan will study the structure of stationary phases used in liquid chromatography. By using a combination of optical spectroscopy of molecular probes in specific solvent environments she will determine the so-called solvatochromic parameters of the system. From this approach the fundamental structure and reactivity of the molecular species at the liquid solid interface can be determined. A better understanding of the mechanisms of molecular interactions which give rise to separations of molecular species in flow will result. Molecular interactions between probe molecules and liquid chromatographic stationary phases will be determined. Optical (uv-visible and infrared spectroscopic band shifts will be measured and analyzed to remove solution phase interferences. Dipolarity-polarizability, hydrogen bond acidity and basicity will allow an understanding of solvent based reactivity and adsorption effects underlying separations and other liquid solid interfacial systems. The particular solvent systems will include methanol, acetonitrile and tetrahydrofuran - water mixtures commonly used in high performance liquid chromatography. Hydrocarbon and phenyl modified silica as well as unmodified silica will be studied. The probe molecules include a series of nitroaniline dyes commonly used to probe solvent solute interactions. Unique capabilities to perform multicomponent analysis and eliminate the contributions of liquid phase effects will allow improvement over the current level of understanding of the dynamics of adsorption at the molecular level in solution.