1251 Wescoe Hall Drive
Phone: (785) 864-3968
Fax: (785) 864-5396
- B.S. 2000, St. Cloud State University
- Ph.D. 2004, University of Wisconsin–Madison
- National Institutes of Health Postdoctoral Fellow, 2005-2007, University of Minnesota
- Silver Anniversary Teaching Award, University of Kansas, 2012
- NSF CAREER Award 2011
- ACS Young Investigator Award – Division of Inorganic Chemistry 2005
- Inorganic Chemistry Research Award, University of Wisconsin-Madison, 2004
Areas of Specialization
Bioinorganic Chemistry, Biomimetic Chemistry, Biophysical Chemistry
Nature uses metalloenzymes containing Mn, Fe, or Cu and oxidants such as molecular oxygen and hydrogen peroxide to carry out remarkable oxidative transformations that are both vital for life and fascinating from a fundamental perspective. The study of such transformations lies at the heart of bioinorganic chemistry. Our research focuses on unraveling the reactivity of manganese-dependent enzymes that catalyze oxidative degradation reactions using molecular oxygen or hydrogen peroxide as oxidants. These reactions also provide the inspiration for our synthetic projects, which include the design of small molecule bleaching catalysts for use in fabric and/or textile applications.
Our laboratory uses a combination of i) reactivity studies of metal ion complexes and enzymes, ii) detailed spectroscopic characterization of transition metal species, particularly unstable intermediates that cannot be characterized using X-ray crystallographic methods, and iii) computational chemistry (see scheme). Spectroscopic methods used in our research include electronic absorption (UV-vis), electron paramagnetic resonance (EPR), and magnetic circular dichroism (MCD) spectroscopies. These tools are particularly powerful when used in conjunction with computational methods, as they permit the characterization of the geometric and electronic structures of fleeting intermediates too unstable to be characterized using standard crystallographic methods. By applying this three-pronged approach to both metalloenzymes and transition metal complexes, we will gain detailed insight into how nature uses molecular oxygen and manganese to oxidize substrates and develop transition metal complexes that can perform "green" oxidation reactions.
Bane, K.; Geiger, R. A.; Chabolla, S. A.; Jackson, T. A. Determination of zero-field splitting parameters for a MnIV center using variable-temperature, variable-field magnetic circular dichroism spectroscopy: Comparison to electron paramagnetic resonance spectroscopy. Inorg. Chim. Acta 2012, 380, 135 – 140. (Young Investigator Award Special Issue.)
Geiger, R. A.; Wijeratne, G.; Day, V. W.; Jackson, T. A. Steric and Electronic Influences on the Structures of Peroxomanganese(III) Complexes Supported by Tetradentate Ligands. Eur. J. Inorg. Chem. 2012, 1598-1608
Geiger, R. A.; Leto, D. F.; Chattopadhyay, S.; Dorlet, P.; Anxolabéhère-Mallart,
E.; Jackson, T. A. Geometric and Electronic Structures of Peroxomanganese(III)
Complexes Supported by Pentadentate Amino-Pyridine and -Imidazole Ligands.
Inorg. Chem. 2011, 50, 10190-10203.
Krause, M. E.; Glass, A. M.; Jackson, T. A.; Laurence, J. S. MAPping the Chiral Inversion and Structural Transformation of a Metal-Tripeptide Complex Having Ni-Superoxide Dismutase Activity. Inorg. Chem. 2011, 50, 2479-2487.
Geiger, R. A.; Chattopadhyay, S.; Day, V. W.; Jackson, T. A. Nucleophilic reactivity of a series of peroxomanganese(III) complexes supported by tetradentate aminopyridyl ligands. Dalton Trans. 2011, 40, 1707 – 1715.
Shi, S.; Wang, Y.; Xu, A.; Wang, H.; Dajian, Z.; Roy, S. B.; Jackson, T. A.; Busch, D. H.; Yin, G. Distinct Reactivity Differences of Metal Oxo and Its Corresponding Hydroxo Moieties in Oxidations: Implications from a Manganese(IV) Complex Having a Dihydroxide Ligand. Angew. Chem. Int. Ed. 2011, 50, 7321-7324.
Chattopadhyay, C.; Geiger, R. A.; Yin, G.; Busch, D. H.; Jackson, T. A. Oxo- and Hydroxomanganese(IV) Adducts: A Comparative Spectroscopic and Computational Study. Inorg. Chem. 2010, 49, 7530 – 7535.
Geiger, R. A.; Chattopadhyay, S.; Day, V. W.; Jackson, T. A. A Series of Peroxomanganese(III) Complexes Supported by Tetradentate Aminopyridyl Ligands: Detailed Spectroscopic and Computational Studies. J. Am. Chem. Soc. 2010, 132, 2821 – 2831.
Krause, M. E.; Glass, A. M.; Jackson, T. A.; Laurence, J. S. Novel Tripeptide Model of Nickel Superoxide Dismutase. Inorg. Chem. 2010, 49, 362 – 364.