RUI:CAS:Reaction Dynamics of Anderson-Type Polyoxometalate Ions in Aqueous Solution: Relating Solid-State Structures with Solution-State Properties

在化学部化学结构、动力学和机理b （CSDM-B）项目和促进竞争性研究的既定项目（EPSCoR）的支持下，克莱顿大学化学和生物化学系的Eric Villa专注于确定简单多金属氧酸盐离子（主要是阴离子金属氧化物簇）的结构特征如何影响它们在水溶液中的反应性。这些多金属氧酸盐（POM）离子的应用范围很广，包括抗病毒/抗肿瘤活性、酸催化、水氧化催化、MRI造影剂、发光和磁性材料，以及潜在的放射性废物处理。本研究的目的是了解POMs在水溶液中的反应方式以及控制其在溶液中的反应性的因素。这个项目的结果数据将使pom能够更好地针对这些重要的应用程序进行调优。该项目让本科生从事基础研究，并对他们进行无机化学方面的训练，包括几种分析技术和仪器方法。本科生也将参与建立和交付一个以无机化学为重点的中学化学夏令营。本项目重点研究安德森型POM离子（XMo6O24z-）在水溶液中的稳定性和反应性。在这里，主要目标是查明原子X身份的变化如何改变水溶液中离子的性质，从而能够将结构-性质关系联系起来。anderson型POM只有三种类型的结构氧，使其成为本科研究人员了解水溶液反应性复杂性的理想结构。重要的是，POMs在水介质中的一般反应性趋势尚未明确，仍有许多未解决的问题：1)什么类型的氧位交换最快？2)什么只影响单个站点，什么影响整个单元？什么结构性质（键长、电荷状态或质子化）与反应性相关？4)观察到的趋势有多普遍？5)至关重要的是，POMs在水中的反应性是否容易预测？6)最后，单一的靶向金属取代如何影响POM与放射性阳离子替代物形成稳定配合物的能力？小型安德森型POMs将允许本科研究人员自信地探索上述问题，收集的数据将允许更好地调整这些离子以适应其令人印象深刻的应用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

WIth support from the Chemical Structure, Dynamics & Mechanisms-B (CSDM-B) Program of the Chemistry Division and the Established Program to Stimulate Competitive Research (EPSCoR), Eric Villa of the Department of Chemistry and Biochemistry at Creighton University is focused on determining how the structural features of simple polyoxometalate ions (predominately-anionic metal-oxide clusters) affect their reactivity in aqueous solution. The range of applications for these polyoxometalate (POM) ions is wide, with properties including antiviral/antitumor activity, acid catalysis, water oxidation catalysis, MRI contrast agents, luminescent and magnetic materials, and potentially radioactive waste treatment. The goal of this research is to understand how POMs react in aqueous solution and what controls their reactivity in solution. The resulting data from this project will allow for POMs to be better tuned for these important applications. This project engages undergraduate students in fundamental research and gains them training in inorganic chemistry, which includes several analytical techniques and instrumental methods. Undergraduate students will also be involved in the set-up and delivery of a middle school chemistry summer camp focusing on inorganic chemistry. This project focuses on understanding the stability and reactivity of Anderson-type POM ions (XMo6O24z-) in aqueous solution. Here, the primary goal is to pinpoint how changes in the identity of atom X alters the ion’s properties in aqueous solution to be able to correlate structure-property relationships. The Anderson-type POM has only three types of structural oxygen, making it an ideal structure for undergraduate researchers to appreciate the complexities of aqueous solution reactivity. Importantly, the general reactivity trends of POMs in aqueous media have not been clearly identified and still have many unanswered questions: 1) What types of oxygen sites exchange the fastest? 2) What affects only a single site versus what affects the entire unit? 3) What structural properties (bond lengths, charge state or protonation) correlate with reactivity? 4) How general are the trends observed? 5) Critically, can the reactivity of POMs in water be easily predicted? 6) Finally, how do single, targeted metal substitutions affect the ability of the POM to make stable complexes with surrogates of radioactive cations for remediation purposes? The small Anderson-type POMs will allow undergraduate researchers to confidently probe the above questions and the data collected will allow for the ability to better tune these ions to their impressive set of applications.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.