RUI: Investigating the Influence of Halogen Ligands on the Ability of Late Gas-Phase Transition Metal Ions to Activate Bonds in Small Substrate Molecules

在化学系化学结构、动力学和机理计划的支持下，中阿肯色大学的威廉·泰勒教授和他的本科生研究团队正在研究小分子与都含有卤素原子(卤素包括氟、氯、溴和碘)的离子之间的反应。这些离子含有过渡金属元素(例如铜、镍或金)。当今许多重要的工业过程都涉及含有过渡金属原子的催化剂。因此，泰勒教授实验室的研究为更广泛的催化领域提供了信息，催化是生产估计90%的所有化学产品的关键部分。催化过程通过直接修复污染物或减少工业化学品生产的环境负担，具有切实的环境效益。参与这项工作的本科生从增加科学保留率的宝贵研究经验中受益，并为他们的各种职业选择做好准备。该项目探索通过配体环境对金属中心的电子修饰对中性分子中键激活的影响。本项目涉及的研究考察了MX+(M=Ni、Cu、Au；X=F、Cl、Br、I)与一些已知的具有强烈温室气体和臭氧消耗作用的卤化化合物的化学。此外，还考察了CuX+和AUX+(X=Cl，F)与甲烷的反应，以探索导致这种丰富但相对惰性的化学资源功能化的低能过程。所有反应都是在气相中使用选择的离子漂移电池反应器进行实验研究的，该反应器在溅射辉光放电源中产生过渡金属离子。然后用所需的卤素对这些金属离子进行化学修饰，选择质量，并将其引入含有感兴趣的中性反应物分子的漂移池中。使用第二个四极杆对反应产物进行分析。实验结果用密度泛函计算和MP2理论进行了补充，以获得对可能的反应机理的更多见解。

In this project supported by the Chemical Structure, Dynamics and Mechanisms Program of the Division of Chemistry, Professor William Taylor of the University of Central Arkansas and his undergraduate research team are studying reactions between small molecules and ions which both contain atoms of halogen elements (the halogens include fluorine, chlorine, bromine and iodine). The ions contain transition metal elements (for example copper, nickel or gold). Many important industrial processes today involve catalysts that contain transition metal atoms. The studies in Professor Taylor's laboratory thus inform the broader area of catalysis, which is a key part of the production of an estimated 90% of all chemical products. Catalytic processes have a tangible environmental benefit by either direct remediation of pollutants or by reducing the environmental burden of industrial chemical production. Undergraduates participating in this work benefit from a valuable research experience that increases retention rates in the sciences, and prepares them for a variety of career choices.The project explores the influence of electronic modifications to metal centers via the ligand environment on bond activation in neutral molecules. Studies addressed in this project examine the chemistry of MX+ (M=Ni, Cu, Au; X=F, Cl, Br, I) with a number of halogenated compounds known to be potent greenhouse gases and ozone depleters. In addition, reactions of CuX+ and AuX+ (X=Cl, F) with methane are examined in order to explore low-energy processes leading to the functionalization of this abundant, yet relatively inert, chemical resource. All reactions are studied experimentally in the gas phase using a selected ion drift cell reactor which generates transition metal ions in a sputtering glow discharge source. These metal ions are then be chemically modified with the addition of the desired halogen, mass selected, and introduced into a drift cell containing the neutral reactant molecule of interest. Analysis of reaction products is carried out using a second quadrupole. Experimental results are complemented computationally with density functional calculations and MP2 theory to gain additional insights into possible reaction mechanisms.