The Behavior of Solvated Electrons in the Presence of Electrolytes: Using Simulation and Experiment to Determine the Hydrated Electron's Structure from Competitive Ion Pairing

电解质存在下溶剂化电子的行为：利用模拟和实验从竞争性离子对确定水合电子的结构

• 批准号: 2247583
• 负责人: Benjamin Schwartz
• 金额: $ 52.5万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2247583&HistoricalAwards=false
• 关键词: Behavior; Solvated; Electrons; Presence; Electrolytes

With support from the Chemical Structure, Dynamics, and Mechanisms-A (CSDM-A) Program in the Division of Chemistry, Professor Benjamin Schwartz of the University of California-Los Angeles is using a combination of theoretical and experimental techniques to investigate the behavior of hydrated electrons in the presence of salts. Hydrated electrons play a critical role in radiation chemistry and electron transfer reactions. Despite the importance of hydrated electrons in chemical reactivity, their structure is uncertain given current limitations in experimental measurements and variations in results from theoretical models. Professor Schwartz and his group will investigate hydrated electrons in the presence of salts to examine how hydrated electrons pair with different salt cations using ultrafast spectroscopic measurements. These results will be directly compared using first-principles simulations to better understand the chemical reactivity of hydrated electrons. Professor Schwartz works with secondary-school teachers and students through an outreach program to help bring modern science to local area high schools. Both experimental and computational studies will be employed to reveal the structure of hydrated electrons. Both mixed quantum/classical simulations, where only the hydrated electron is treated quantum mechanically, and ab initio simulations, where the entire system is treated by density functional theory (DFT), will be used to understand the thermodynamics of simulated hydrated electrons paired with different cations. Ultrafast spectroscopy experiments will be used to measure the absorption spectrum of hydrated electrons in the presence of different salts thereby providing a direct measure of the degree of ion pairing that can be compared with the different simulation models. Additional measurements of photoexcited hydrated electrons have the potential to provide a detailed understanding of how the presence of salts alters the dynamics and thus the structure of hydrated electrons paired with different cations. By using both experiments and simulations, the reactive chemistry of pairs of hydrated electrons and a direct connection between structure and reactivity will be developed.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在化学结构，动力学和机制-A（CSDM-A）计划中的支持下，加州大学洛杉矶分校的本杰明·施瓦茨教授正在使用理论和实验技术的结合来研究在盐下水合电子的行为。水合电子在辐射化学和电子转移反应中起关键作用。 尽管水合电子在化学反应性中的重要性，但考虑到实验测量中的当前局限性以及理论模型结果的变化，它们的结构仍不确定。 Schwartz教授和他的小组将在存在盐的情况下研究水合电子，以检查水合电子如何使用超快的光谱测量结果对不同的盐阳离子搭配。这些结果将使用第一原理模拟直接比较，以更好地了解水合电子的化学反应性。 Schwartz教授与二级教师和学生通过外展计划合作，以帮助将现代科学带到当地高中。实验研究和计算研究都将用于揭示水合电子的结构。混合量子/经典模拟，只有水合电子被机械处理量子，并且从头算模拟（通过密度函数理论（DFT）处理）将用于了解模拟水合电子的热力学与不同阳离子配对。超快光谱实验将用于在存在不同盐的存在下测量水合电子的吸收光谱，从而直接衡量可以将可以与不同的模拟模型进行比较的离子配对程度。光激发水合电子的其他测量可能会提供详细了解盐的存在如何改变动力学，从而改变与不同阳离子配对的水合电子的结构。通过使用实验和仿真，将开发出水合电子对的反应性化学和结构和反应性之间的直接联系。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点评估和更广泛的影响来审查标准的评估。