Our research is focused on applying state-of-the-art techniques in microwave spectroscopy to solve problems in astrochemistry and in analytical chemistry. Our research group at UC Davis applies microwave spectroscopy to study kinetics of chemical reactions that occur in space, and explores new uses of microwave spectroscopy for automated chemical analysis.

Astrochemistry is the study of the chemical processes that occur in diverse regions of space. Powerful telescope facilities, such as the Hubble Space Telescope and the Atacama Large Millimeter Array, provide spectacular data about astronomical objects like interstellar clouds and protoplanetary disks, but challenging experimental work that simulates the extreme conditions of space is required in order to accurately interpret these observations. The Crabtree lab uses a technique called chirped-pulse Fourier Transform Microwave (CP-FTMW) spectroscopy together with supersonic molecular beam methods to study the rates of chemical reactions under space-like conditions. Using the rate data obtained from these experiments, computer modeling can be used to interpret telescope observations. Through this combination of laboratory experiments, computer techniques, and collaborations with astronomers, the Crabtree group aims to improve our understanding of the origin of life on Earth and to assess the prospects for the development of life elsewhere in the universe.

The same microwave technology that enables these astrochemical studies may also have important applications in analytical chemistry. Professor Crabtree has recently developed a new method called Automated Microwave Double Resonance (AMDOR) spectroscopy to enable automatic identification of molecules in complex mixtures, even if they have never been previously observed. AMDOR is a hands-off technique that uses microwaves to generate an effective 2D molecular barcode unique to the exact three-dimensional structure of each molecule in a sample, providing a powerful complement to existing analytical methods such as mass spectrometry and nuclear magnetic resonance spectroscopy. The Crabtree group is currently exploring machine-learning-based algorithms to automatically read and interpret these barcodes in order to speed up analysis and decrease sample consumption. If successful, AMDOR may be routinely used to characterize new molecules synthesized in chemical laboratories, as well as in forensic applications to identify new or unknown molecules that may be used as designer drugs or sports dopants.

Recent Publications

Showing most recent 3 publications

Barreau, Lou; Martinez, Oscar; Crabtree, Kyle N.; Womack, Caroline C.; Stanton, John F.; McCarthy, Michael C.
Oxygen-18 Isotopic Studies of HOOO and DOOO
J. Phys. Chem. A. 2017, 121 (33), 6296-6303. http://dx.doi.org/10.1021/acs.jpca.7b05380.

Law, Charles J.; Milisavljevic, Dan; Crabtree, Kyle N.; Johansen, Sommer L.; Patnaude, Daniel J.; Margutti, Raffaella; Parrent, Jarod T.; Drout, Maria R.; Sanders, Nathan E.; Kirshner, Robert P.; Lathan, David W.
TRES survey of variable diffuse interstellar bands
Mon Not R Astron Soc. 2017, 470 (3), 2835-2844. http://dx.doi.org/10.1093/mnras/stx1398.

Crabtree, Kyle N.; Martin-Drumel, Marie-Aline; Brown, Gordon G.; Gaster, Sydney A.; Hall, Taylor M.; McCarthy, Michael C.
Microwave spectral taxonomy: A semi-automated combination of chirped-pulse and cavity Fourier-transform microwave spectroscopy
J. Chem. Phys.. 2016, 144 (12), 124201. http://dx.doi.org/10.1063/1.4944072.