Kinetics and Energetics of Gas Phase Metal Cluster Catalysis

在这个由化学部实验物理化学计划支持的项目中，Ervin将研究气相过渡金属团簇和吸附物之间的相互作用。 利用能量分辨碰撞诱导解离和时间分辨光解离实验测量了吸附物在团簇上的结合能。 统计速率理论应用于集群解离数据，以获得解吸能。 主要目标包括利用光解离动力学技术获得裸金属簇和簇上吸附物的结合能;探索气相过渡金属簇作为实际催化剂;以及检查与催化相关的小簇/配体系统。 本计画将使用导引离子束串联质谱仪来收集资料，所测得的资料对于确定催化反应的机制和绘制反应路径都是重要的。 这里研究的簇是催化系统的模型，因为它们模拟了工业过程中使用的催化剂中的反应中心的小金属微晶。 气相簇本身也可以作为催化剂，如在一氧化碳氧化成二氧化碳的铂簇阴离子。

In this project supported by the Experimental Physical Chemistry Program of the Chemistry Division, Ervin will investigate the interactions between gas-phase transition metal clusters and adsorbates. Energy-resolved collision-induced dissociation and time-resolved photodissociation experiments are used to measure the binding energies of adsorbates on the clusters. Statistical rate theory is applied to the cluster dissociation data to obtain desorption energies. Major thrusts include exploitation of photodissociation dynamics techniques to obtain binding energies of bare metal clusters and of adsorbates on clusters; exploration of gas-phase transition metal clusters as actual catalysts; and examination of small cluster/ligand systems of relevance to catalysis. A guide ion beam tandem mass spectrometer will be used to gather the data.The data measured in this project are important for determining catalytic reaction mechanisms and for mapping out reaction paths. The clusters under study here are models for catalytic systems because they mimic small metal crystallites that comprise the reaction centers in catalysts used in industrial processes. Gas phase clusters themselves can also act as catalysts, as in the oxidation of carbon monoxide to carbon dioxide by platinum cluster anions.