Intrinsic Barriers as a Guide to Rates and Mechanisms of Reactions on Solid Surfaces

固有势垒作为固体表面反应速率和机制的指南

• 批准号: 9610115
• 负责人: Richard Masel
• 金额: $ 20.5万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 1999-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9610115&HistoricalAwards=false
• 关键词: Intrinsic; Barriers; Guide; Rates; Mechanisms

ABSTRACT CTS 9610115 Richard I. Masel Professor Richard I. Masel, of the University of Illinois, Urbana-Champaign, is being funded by the Chemical Reactions Processes-Kinetics and Catalysis program to continue his studies of adsorption of small organic molecules on model transition metal surfaces. He will continue to develop a theoretical approach to predicting surface chemical mechanisms. The basic hypothesis of the theoretical model is that intrinsic barriers calculated for decomposition reactions in the gas phase are equal to the intrinsic barriers for those decompositions on surfaces. Experimentally, the model is tested with EELS and TPD spectroscopies. In this work, Masel proposes to do more detailed characterization of the intrinsic barriers for C-C, C-O, C-H and O-H bond scissions, in terms of parameters such as substituent groups in the organic molecules or presence of coadsorbates, and nature of the chemisorbing surface. It is focused on the measurement of heats of reaction, bond energies, and intrinsic activation barriers for specific test reactions, for which model predictions will be made with the aid of computational quantum chemistry. The role of net charges in the intrinsic barrier model will also be assessed. This research is of major significance for the theory and practice of catalysis and surface chemistry.

摘要 CTS 9610115 Richard I. Masel 伊利诺伊大学厄巴纳-香槟分校的 Richard I. Masel 教授正在接受化学反应过程动力学和催化计划的资助，继续研究小有机分子在模型过渡金属表面上的吸附。 他将继续开发预测表面化学机制的理论方法。 理论模型的基本假设是，计算出的气相分解反应的固有势垒等于表面分解反应的固有势垒。 实验上，该模型通过 EELS 和 TPD 光谱进行测试。 在这项工作中，Masel 建议根据有机分子中的取代基或共吸附物的存在以及化学吸附表面的性质等参数，对 C-C、C-O、C-H 和 O-H 键断裂的内在势垒进行更详细的表征。 它专注于测量特定测试反应的反应热、键能和固有活化能垒，并借助计算量子化学进行模型预测。 还将评估净电荷在本征势垒模型中的作用。 该研究对于催化和表面化学的理论和实践具有重要意义。