Water-Mediated Interactions

该奖项由化学系化学结构、动力学和机制（CSDM-A）项目资助，科罗拉多普渡大学的Dor Ben-Amotz教授和他的研究生和本科生同事正在研究水对溶解在其中的物质的行为的影响。水介导的相互作用在生物、医学、环境和材料化学中发挥着核心作用，然而大多数这种相互作用的大小（在某些情况下甚至是迹象）还没有被实验确定。水合壳光谱测量与理论和模拟分析相结合，量化了自由能驱动力和与水介导的溶质聚集（如溶解的醇、盐、气体、羧酸和表面活性剂）相关的结构变化。水介导的相互作用的定量实验和理论研究可以促进对生化系统和自组装装置的理解。该研究为研究生和本科生提供了参与项目的培训和指导机会。Ben-Amotz和他的研究小组将拉曼光谱与多元曲线分辨率（Raman- mcr）相结合，以测量水溶质水化壳聚集引起的变化。采用一种新的序列自建模曲线分辨率策略来量化非聚集和聚集溶质种类的浓度变化。随机混合和分子动力学模拟，结合有限晶格和加权随机混合理论分析策略，分离了直接和水介导的，以及能量和熵的，平均力聚集势的贡献，这些贡献与溶质对之间的二元相互作用和多个溶质之间的合作相互作用有关。

In this award, funded by the Chemical Structure, Dynamics and Mechanisms (CSDM-A) Program of the Division of Chemistry, Professor Dor Ben-Amotz of Purdue University of Colorado and his graduate and undergraduate student colleagues are studying the way water influences the behavior of substances dissolved in it. Water-mediated interactions play a central role in biological, medicinal, environmental, and materials chemistry, and yet the magnitudes (and in some cases even the signs) of most such interactions have not been experimentally determined. Hydration-shell spectroscopic measurements are combined with theoretical and simulation analysis to quantify the free energy driving forces and the structural changes associated with the water-mediated aggregation of solutes such as dissolved alcohols, salts, gases, carboxylic acids, and surfactants. The quantitative experimental and theoretical studies of water-mediated interactions may advance the understanding of biochemical systems and of self-assembled devices. The research provides training and mentoring opportunities for graduate and undergraduate students, as they participate in the project.Prof. Ben-Amotz and his research group conducts combined Raman spectroscopy with multivariate curve resolution (Raman-MCR) to measure aggregation-induced changes in hydration-shells of aqueous solutes. A new sequential self-modeling curve resolution strategy is used to quantify changes in the concentrations of non-aggregated and aggregated solute species. Random mixing and molecular dynamics simulations, combined with finite lattice and weighted random mixing theoretical analysis strategies are used to separate direct and water-mediated, as well as energetic and entropic, contributions to the aggregation potential of mean force associated with both binary interactions between pairs of solutes and cooperative interactions between multiple solutes.