Determining Mechanisms and Energetics of Alkane Activation and Coupling by Transition Metal Ions

在化学系化学结构、动力学和机制计划-A的支持下，马萨诸塞州大学的Ricardo梅斯教授将研究过渡金属离子和金属簇离子如何与甲烷和乙烷反应，并催化它们转化为更有用的工业化学品。天然气主要是甲烷。在室温下，即使在压力下，甲烷仍然是气体。这限制了它作为运输燃料的用途。这些研究将着眼于将甲烷转化为更大的碳氢化合物的基本反应，这些碳氢化合物在室温下是液体，因此是更好的车辆燃料。这项工作的更广泛的影响包括改进催化剂的潜在好处，以及培训研究生和本科生的技术，如激光光谱和质谱。最根本的是，学生从事这项研究将吸收解决问题，实验设计，收集和分析数据，并在沟通他们的结果的技能。梅斯教授还将通过尤里卡帮助介绍八年级的女孩科学研究！在该奖项下进行的研究将使用各种技术来表征过渡金属离子和簇离子与一个或多个甲烷或乙烷分子反应的反应物、中间体和产物。动力学研究的目标是测量反应速率，并将反应性与离子前沿分子轨道的性质相关联。振动光谱学将用于鉴定反应产物和稳定的中间体。总之，这些研究预计将有助于加强对过渡金属C-H键活化和C-C偶联机制的基本理解，最终目标是改进天然气物流中相对不反应的主要组分中C-H/C-C键活化的方法。 金属-烷基离子的互补离子光碎片成像研究将用于确定精确的共价键强度，测量光解离动力学和检查自旋禁戒过程。该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

WIth support from the Chemical Structure, Dynamics, and Mechanisms Program-A of the Chemistry Division, Professor Ricardo Metz of the University of Massachusetts, Amherst will study how transition metal ions and metal cluster ions react with methane and ethane and catalyze their conversion to more industrially useful chemicals. Natural gas is mostly methane. At room temperature methane remains a gas, even under pressure. This limits its usefulness as a transportation fuel. These studies will look at the fundamental reactions involved in converting methane to larger hydrocarbons that are liquids at room temperature and thus are better fuels for vehicles. The broader impacts of this work include potential benefits from improved catalysts as well as training graduate and undergraduate students in techniques such as laser spectroscopy and mass spectrometry. Most fundamentally, students engaged in this research will assimilate skills in problem solving, experimental design, the collection and analysis of data, and in communicating their results. Professor Metz will also help to introduce eighth-grade girls to science research through the Eureka! program.The research studies being conducted under this award will use a variety of techniques to characterize the reactants, intermediates and products of the reactions of transition metal ions and cluster ions with one or more methane or ethane molecules. Kinetics studies are targeted at measuring the rates of the reactions and correlating reactivity with properties of the frontier molecular orbitals of the ions. Vibrational spectroscopy will be employed to identify both reaction products and stable intermediates. Taken together, these studies are expected to contribute to enhanced fundamental understanding of the mechanisms of C-H bond activation and C-C coupling by transition metals, with the ultimate goal of improving methods for C-H/C-C bond activation in relatively unreactive principal components of natural gas streams. Complementary ion photofragment imaging studies of metal-alkyl ions will be utilized to determine precise covalent bond strengths, measure photodissociation dynamics and to examine spin-forbidden processes.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.