Sophia E. Hayes
Campus Box 1134
Research Interests
Optically-pumped Nuclear Magnetic Resonance (OPNMR): The goal of our research is to probe the interplay between dopants, defects, and interfaces and electronic properties of various semiconductors and other optically active materials. To that end, we are developing experimental strategies based on modern solid-state nuclear magnetic resonance (NMR) spectroscopy, which help elucidate the structure and dynamics of complex systems (e.g., thin films, nanoclusters, and amorphous materials).
I. Optically-polarized NMR (OPNMR): OPNMR combines laser excitation with NMR detection. The laser creates polarized electronic spins that couple to nuclear spins. The polarized nuclear spins can then be detected by NMR. We are applying optical pumping techniques to systems of semiconductors to better understand their opto-electronic properties: semiconductor quantum wells, nanoclusters and quantum wires, and opto-electronic devices.
II. Hardware for combined OPNMR and optically-detected NMR (ODNMR): as with OPNMR, ODNMR utilizes laser excitation coupled with NMR where the luminescence is recorded rather than the rf signal. We are designing an integrated system to record both types of information in a single apparatus.
III. Carbon capture and sequestration (CCS) is currently being pursued as a means of reducing net carbon dioxide (CO2) output from power plant sources by capturing the CO2 then utilizing it or sequestering it. Geological sequestration and chemical utilization of CO2 as a feedstock chemical are actively being explored as possible mechanisms for reducing net anthropogenic CO2 release. We have developed an in situ 13C NMR method of monitoring these reactions as they happen at high pressures (up to 250 bar) and temperature (up to 250 °C). These reactions carbonation reactions are very pH dependent, so we have additionally developed the capability of extracting pH information from the 13C NMR data obtained throughout the reaction. We are now investigating how pH controls the reaction and how to use it as an indicator of reaction progress and solid carbonate product purity.
Selected Publications
Surface, J. Andrew; Skemer, Philip; *Hayes, Sophia E.; *Conradi, Mark S. "In Situ Measurement of Magnesium Carbonate Formation from CO2 Using Static High-Pressure and -Temperature 13C NMR" Environ. Sci. Technol., 2013, 47, 119?125. doi: 10.1021/es301287n
Nieuwendaal, Ryan; Mattler, Sarah; Bertmer, Marko; *Hayes, Sophia "Single Crystal-to-Single Crystal Photoreactions: Measuring the Degree of Disorder in the [2+2] Photodimerization of trans-Cinnamic Acid using Single Crystal 13C NMR Spectroscopy" J. Phys. Chem. B 2011, 115, 5785-5793. doi: 10.1021/jp200952g. View article...
Hammerstroem, Douglas; Burgers, Mark; Chung, Stephen; Guliants, Elena; Bunker, Christopher; Wentz, Katherine; Hayes, Sophia;Buckner, Steven; *Jelliss, Paul "Aluminum Nanoparticles Capped by Polymerization of Alkyl-Substituted Epoxides: Ratio-Dependent Stability and Particle Size" Inorg. Chem. 2011, 50, 5054-5059. doi: 10.1021/ic2003386. View article...
Wang, Wei; Wentz, Katherine M.; Hayes, Sophia E.; Johnson, Darren W.; *Keszler, Douglas A. "Synthesis of the Hydroxide Cluster [Al13(μ3-OH)6(μ-OH)18(H2O)24]15+ from an Aqueous Solution" Inorg. Chem. 2011, 50, 4683-4685. doi: 10.1021/ic200483q.
Ramaswamy, Kannan; Mui, Stacy; Crooker, Scott A.; Pan, Xingyuan; Sanders, Gary D.; Stanton, Christopher J.; *Hayes, Sophia E. "Optically Pumped NMR: Revealing spin-dependent Landau level transitions in GaAs" Phys. Rev. B 2010, 82, 085209, 1-5. doi: 10.1103/PhysRevB.82.085209.
*Hayes, Sophia E.; Mui, S.; Ramaswamy, K. "Optically pumped nuclear magnetic resonance of semiconductors," J. Chem. Phys. 2008. 128, 052203/1-17. doi: 10.1063/1.2823131
Ramaswamy, K.; Tulsky, E.G.; Long, J.R.; Kao, J. L.-F.; *Hayes, S.E. "Determination of 77Se-77Se and 77Se-13C J-coupling Parameters for the Selenocyanide Clusters [Re5OsSe8(CN)6]3- and [Re4Os2Se8(CN)6]2-" Inorg. Chem. 2007, 46, 1177-1186. doi:10.1021/ic061571g
Ma, G.; Fischer, A.; Ramaswamy, K.; *Hayes, S.E. "Cd(II)-ethlenediamine Mono- and Bimetallic Complexes-Synthesis and Characterization by 113Cd NMR Spectroscopy and Single Crystal X-ray Diffraction" Inorg. Chim. Acta 2005, 358, 3165-3173. doi:10.1016/j.ica.2005.04.029
Awards
Chair-Elect, Gordon Research Conference on Magnetic Resonance, 2013 (Vice Chair, 2011)
2009, Regitze R. Vold Memorial Prize
2007-2009, Alfred P. Sloan Research Fellow
2008, ACS Progress/Dreyfus Lectureship
2004, Washington University Graduate Student Senate Special Recognition for Excellence in Mentoring
2003, NSF Early Career Development (CAREER) Award
2001, Alexander von Humboldt Research Fellow, Dept. of Physics, University of Dortmund, Germany
1998-2000, Directorate Postdoctoral Fellow, Lawrence Livermore National Laboratory
1999, Chemistry and Materials Science Directorate Award, Lawrence Livermore National Lab
Courses
Chem 470 Inorganic Chemistry Lab
Chem 461 Inorganic Chemistry
Chem 111 General Chemistry
Chemistry 541 Advanced Chemistry (Group Theory & Spectroscopy)
Physics 534 Magnetic Resonance