Theoretical Studies of Inorganic and Organometallic Systems

无机化学、生物无机化学和金属有机化学项目的这一奖项支持德克萨斯农工大学化学系的迈克尔·B·霍尔博士进行的与催化相关的理论研究。与催化中的四个基本步骤相关的体系将被研究：氧化加成、取代、迁移插入和原子转移。详细的动力学研究的早期阶段的C-H键活化的一个铑的羰基络合物。连接两个提议的溶剂化中间体的过渡态的性质和能量将被确定。其他的研究将集中在Dirhodium催化的环化反应和Ru催化的炔烃和烯烃二聚反应。非经典二氢络合物和经典氢化物之间的转换将被模拟。氧的转移和插入将在模拟钼酶的模型系统中进行检验。计算结果将与已知的实验结果进行比较。非局域密度泛函理论(DFT)和多组态自洽场(MCSCF)方法，特别是广义分子轨道方法(GMO2)将用于稳定分子、反应中间体和过渡态的全梯度几何优化。GMO2方法非常适用于过渡金属。更高水平的方法将被用来确定势能面上的临界点。许多重要的工业反应的详细催化机理尚不清楚。在这项研究中，将使用分子电子态及其反应路径的理论计算来开发反应性模型，并将其与实验结果进行比较。这可能有助于改进催化剂的开发。

This award in the Inorganic, Bioinorganic, and Organometallic Chemistry Program supports theoretical studies related to catalysis by Dr. Michael B. Hall of the Chemistry Department, Texas A&M University. Systems related to four fundamental steps in catalysis will be investigated: oxidative-addition, substitution, migratory-insertion, and atom transfer. Detailed kinetics of the early stages of C-H bond activation by a rhodium carbonyl complex will be studied. The nature and energy of the transition states connecting two proposed solvated intermediates will be determined. Other studies will concentrate on dirhodium catalyzed cyclizations and ruthenium catalyzed alkyne and alkene dimerizations. Transformations between non-classical dihydrogen complexes and classical hydrides will be modeled. Oxygen transfer and insertion will be examined in a model system that mimics molybdenum enzymes. Calculational results will be compared with known experimental results. Non-local density functional theory (DFT) and multiconfiguration self-consistent field (MCSCF) methods, especially generalized molecular orbital method (GMO2), will be used for full-gradient geometry optimization of stable molecules, reaction intermediates, and transition states. The GMO2 method is well-suited to transition metals. Higher level methods will be used to determine critical points on potential energy surfaces.Detailed mechanisms for catalysis of many important industrial reactions are not known. In this study, theoretical calculations of the electronic states of molecules and their reaction pathways will be used to develop models for reactivity that will be compared to experimental results. This could aid in the development of improved catalysts.