Associate Professor of Chemistry
BS Rhodes College 1991
Ph.D. Cornell University 1996
Dr. Clayton Spencer’s teaching and research interests
I teach general chemistry and upper-level courses in physical and analytical chemistry. I enjoy the general chemistry course as it is an opportunity to introduce the fundamentals of this fascinating science to new students. This course can be a challenge for many students given the wide range of abstract topics the course includes. I enjoy exploring new ways to meet the challenges that students face in a course like general chemistry and in helping them to learn the concepts well and become interested in the topics. I particularly like including lab experiences where students can practice working like a scientist by designing their own experiments, making their own discoveries, and figuring out for themselves what all the data means. I also enjoy teaching the upper-level courses where I can focus on the physics of why chemical phenomena happen the way that they do. In the analytical sequence of courses, I enjoy helping students learn how to apply the methods thoughtfully and understand why the methods and instrumentation works the way that they does.
I have two areas of research and several projects in each area.
- Computational Chemistry. As a computational chemist by training, my research focuses on using fundamental physical theory to model, on a computer, important chemical phenomena in order to gain deeper insight into the specific details of the process. There are two current projects and both use quantum chemical electronic structure methods to compute properties of molecules and chemical reactions. (a) The first project examines the relative effects that surface structure and electronic relaxation have on the reaction of molecular hydrogen with defect sites on silicon surfaces. Such reactions are important to the electronics industry in the passivation of semiconductors and are related to radiation damage that electronic devices suffer in satellites and other space-based devices. (b) The second project is in collaboration with Professor Chandler in Organic Chemistry. Here we attempt to model the reactions relevant to the catalysts and other synthetic targets that he is designing. Our goal is to compute the reaction energetics including the magnitude of the energy barrier to the reaction and also to gain theoretical support for probable mechanisms that explain how the reaction happens in a detailed manner.
- Chemical Analysis. In collaboration with Dr. Zettler and other members of the Biology department, my research in the area of chemical analysis focuses on using our available analytical tools – gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) – to profile the small molecule metabolites in a sample of tissue from an organism. Metabolites are the small molecules that organisms use and produce as part of their metabolism. The process of determining which metabolites are present and their respective amounts is called metabolomics. A metabolic profile can be thought of as a snapshot of an organism’s biochemistry in the tissue at the time of sampling. Experimentally, measuring a metabolic profile consists of adapting and developing chemical analysis techniques to identify as many of the metabolites present in a sample as possible and their respective amounts in a reliable way. By comparing metabolic profiles using statistical analysis, we can observe changes in an organism’s biochemistry as a function of growth and development, environmental conditions, or stress. Furthermore, differences in metabolic profiles among and between organisms can point to important differences in their expressed biochemistry. This kind of information complements that on an organism’s genetic make-up (genomics) and protein make-up (proteomics).