This Research award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports work by Professor Michael B. Hall at Texas A&M University to carry out fundamental/basic studies on the mechanisms of transition metal catalyzed reactions involving the activation of both hydrocarbons and hydrogen by using density functional theory and ab initio quantum calculations. Activation of the carbon-hydrogen and carbon-carbon bonds in hydrocarbons is the first step in catalytic cycles that produce useful, high-value products. Furthermore, with vast methane reserves, the direct conversion of methane to other more reactive and useful products is an important step for our future energy and material needs, and the activation, production, and storage of molecular hydrogen are keys in the use of hydrogen as a secondary fuel source. These calculations provide an understanding of these important reactions in sufficient detail to contribute to the development of new catalysts. The close coupling of theory and experiment through collaborative arrangements, a hallmark of this award, stimulates rapid progress on these important chemical problems and keeps the effort focused on the most important questions. The students and postdoctoral associates at Texas A&M University receive essential education and training such that they will be well equipped to meet future scientific challenges, while the large number of collaborators now associated with the laboratory brings the educational aspects to a much broader audience. In addition this award supports a faculty collaborator and one undergraduate student from Prairie View A&M University (HBCU). This award also supports the development of the Fenske-Hall electronic structure method with its own graphical user interface that can be incorporated into teaching both undergraduate and graduate students about chemical bonding concepts. The teaching value of this program is extremely high as it is the only simple technique available that combines (1) a free graphical user interface, (2) all elements capability (including transition metals) and (3) fragment analysis and construction, which clarifies the bonding in large systems by simplifying their construction from simple metal-ligand fragments. Finally, this research lays the foundations for improving catalytic reactions that are essential in developing new energy sources and in efficiently utilizing our hydrocarbon reserves.
Through this award funded by the Division of Chemistry, Professor Michael B. Hall at Texas A&M University, College Station, solved several important problems of current interest in catalytic reactions and fundamental steps in catalytic cycles that involved the activation of alkanes and dihydrogen by using modern computational modeling. Understanding catalytic cycles is important to most industrial and natural processes. The research studied both natural enzymatic systems, particularly the hydrogenase enzymes, and totally synthetic model complexes for the hydrogenase systems. Understanding how nature and artificial systems cleave and reassemble hydrogen can help in the development of a hydrogen economy, which may be an important component of a pollution-free energy in the future. In a second major thrust of this research, both thermal and photochemical activation of carbon-hydrogen bonds in alkanes were modeled. Carbon–hydrogen bond activation plays a key role in making better use of our limited resources, particularly natural gas and in transforming many small molecules into important commercial products such as plastics and fabrics. The close coupling of theory and experiment through collaborative arrangements stimulated rapid progress on these important chemical problems. In this study the modeling involved full-gradient geometry optimizations with non-local density-functional theory and ab initio energy calculations, primarily coupled cluster and multireference configuration interaction. The close collaboration with experimental groups also provided frontier problems as testing grounds for new functional and methodological developments. In addition to the education of students and postdoctoral associates at Texas A&M University, the large number of collaborators now associated with the laboratory has brought the educational aspects to a much broader audience. In addition to the intellectual value in the further development of the Fenske-Hall method, its simple graphical users interface (GUI) was developed to allow the method to be easily used by a wider audience and to be incorporated into teaching both undergraduate and graduate students about chemical bonding concepts. The teaching value of this Fenske-Hall/GUI is extremely high as it is the only simple technique available that combines all-elements capability (including transition metals) and fragment analysis and construction, which clarifies the bonding in large systems by simplifying their construction from simple metal-ligand fragments.
