McMahon Group Research
Overview
Our interdisciplinary research program impacts diverse areas of chemical and physical science, including astrochemistry, flames and combustion, soot formation, atmospheric chemistry, lithography, plasmas, and electrical discharge. The inherent complexity of these chemical environments demands an integrated study involving organic chemistry, molecular spectroscopy, and quantum chemistry. Through these combined efforts, it is possible to generate and characterize the prototypical reactive intermediates in organic chemistry and to probe their structure and spectroscopy in unprecedented detail. These fundamental structural, spectroscopic, and mechanistic data provide a foundation for understanding the chemistry of organic matter in harsh environments.
Our research reaches beyond chemistry and cuts across diverse areas of contemporary science. In the area of combustion chemistry, the determination of accurate equilibrium structures of reactive intermediates provides important benchmarks for prototypical molecules. In the area of astrochemistry, the program addresses fundamental questions concerning the chemical nature of what is now recognized to be the dominant reservoir of organic compounds in the universe. A deeper understanding of the organic chemistry of space may carry implications concerning origin of life. In the area of atmospheric chemistry of Titan and primitive Earth, fundamental mechanistic questions associated with the splitting of molecular nitrogen is probed.
Our collaborative research projects create an environment for training the next generation of scientists in the study of complex chemical problems as part of an interdisciplinary research team. Students are immersed in an enviroment of exceptional breadth, encompassing organic chemistry, reaction mechanism, quantum chemistry, molecular spectroscopy, and theoretical chemical physics. They encounter the intellectual challange of mastering multiple disciplines, and they confront the challenging problem of communicating across divisional boundaries.
Matrix Isolation
The McMahon group combines synthetic organic chemistry with spectroscopy and computational chemistry to study reactive intermediates and molecules of interest in the interstellar medium. To study extremely reactive molecules, such as carbenes and highly-strained rings, a technique known as matrix isolation is used. Essentially, the diazo precursor to the carbene is generated in the gas phase and then frozen in argon at 10 K on a spectroscopic window. Irradiation yields the carbene, whose identity is proven by the use of computational chemistry and by IR, UV, and ESR spectroscopy. The matrix can then be further irradiated with various wavelengths of light to yield the photo-rearrangements of these molecules.
Group Research Poster (PDF File)
Last updated July 7, 2008.
