In this project supported by the Chemical Structure, Dynamics, and Mechanisms Program of the Division of Chemistry, Professor Christopher Cramer of the University of Minnesota and his research group will employ quantum chemical computational methods to explore a number of important chemical processes, including the activation of C-H bonds and molecular O2 and N2O, and water splitting by various mono-and bimetallic catalyst systems. As part of the investigation into these specific chemical systems, the Cramer team will also compare the results of density functional theory (DFT) calculations with the results of experiment and/or multireference wave function theory calculations. The goal of this comparison is to validate the application of the simpler DFT approach(es) to complex problems involving near degeneracies of frontier orbitals. Finally, Prof. Cramer will continue work on the incorporation of continuum solvation models into DFT and time-dependent DFT (TD-DFT).
In addition to advancing our understanding of the specific chemical systems mentioned above, Prof. Cramer's research program will advance the fields of catalysis and computational chemistry, and possibly have implications for energy conversion technology. The research program will also provide a rich environment for the training of undergraduate and graduate students, and outreach activities by Prof. Cramer and his group will introduce the world of computational chemistry to audiences ranging from high school to post-secondary levels. Finally, Prof. Cramer will include results from his research in the next edition of his textbook, "Essentials of Computational Chemistry," and will make any software resulting from this work available to other researchers, thus broadening the impact of the project.
In Chemistry, "sustainability" refers to the creation and adoption of processes that efficiently generate energy or materials at minimal cost to the environment as a whole. Examples of such processes include, for instance, the transformation of abundant solar energy into chemical fuels, or the reduction in energy costs required to turn one material into another through the use of specifically engineered catalysts. NSF support permitted us to develop and apply theoretical models to understand the fundamental chemical mechanisms of a number of different chemical processes, including the generation of hydrogen gas as a fuel from the oxidation of water, the reduction of the greenhouse gas carbon dioxide to the useful chemical formic acid, and the activation of molecular oxygen to accomplish chemistry mimicking that carried out by enzymes, e.g., taking hydrocarbons to value-added commodity chemicals. Essentially all of the theoretical work enabled by this support was undertaken in collaboration with experimental groups in the United States and around the world. The modeling efforts rationalized experimental observations and informed next-generation catalyst design efforts to improve activities and characteristics of the various systems studied. As part of the funded work, software was created to make new computational models available as tools to the broader scientific community. In particular, software implementing the CMx charge models and SMx solvation models was made widely available to the modeling community through such freely distributed codes as Amsol, Gamessplus, Hondoplus, Omnisol, and Smxgauss. The models were also incorporated into the latest versions of the commercial codes Jaguar and Q-Chem, and the CM5 and SMD solvation models also appear in Gaussian 09. Both the models and the codes have found widespread use in the computational community. In addition to the scientific accomplishments made possible with this NSF support, the PI developed and twice taught a massive open online course (MOOC) entitled Statistical Molecular Thermodynamics to approximately 8,000 students who enrolled free of charge on the Coursera platform. Roughly 1,700 students engaged with all components of the 8 week course; almost 900 worked to earn certificates of accomplishment. All course videos continue to be freely available on YouTube and the content is being used to teach the first 8 weeks of the equivalent University of Minnesota course. In addition, the PI developed and taught curriculum within the University of Minnesota’s Exploring Careers in Engineering and the Physical Sciences (ECEPS) initiative. ECEPS is a series of week-long summer outreach programs organized by the University of Minnesota’s College of Science and Engineering. ECEPS is targeted to high-school students, with special emphasis on cohorts currently underrepresented in critical STEM fields. In particular, a one-day ECEPS curriculum, with mentored software training, was developed to familiarize participants with molecular modeling and its applications to the prediction of molecular shapes and bulk properties.
