Dennis L. Lichtenberger

Honors

• Associate Editor, Organometallics, 2008
• Ninth Annual University Graduate and Professional Education Teaching and Mentoring Award, 2008
• University of Arizona Faculty of Science Distinguished Teaching Award, 1994
• Alfred P. Sloan Research Fellowship, 1979-1983

Education and Appointments

• B.S. 1969, Indiana University, Bloomington
  
• Ph.D. 1974, University of Wisconsin, Madison
  

Research Interests

• Inorganic
  
• Computational
  
• Gas Phase Structure and Spectroscopy
  
• Bioinorganic
  
• Catalysis and Reaction Dynamics
  
• Instrumentation
  
• Materials Synthesis and Characterization
  
• Organometallic and Coordination Chemistry
  
• Surface Science
  

Research Summary

A special feature of this research program is the use of photoelectron spectroscopy to obtain precise experimental measures of the energies required to remove electrons from large molecules and materials. These energies and other features of the photoionization process reveal the factors that control electron movement and determine chemical reactivity, electron transfer behavior, optoelectronic properties, and more.

The research as depicted in the figure above offers opportunities in high-resolution gas-phase spectroscopy, ultra-high vacuum surface analysis, computational chemistry, synthesis of new molecules and materials, and/or development of new methods and instrumentation. Students choose the projects in which they are most interested, and may focus on inorganic, physical, analytical, organic, or biological chemistry areas. Examples of chemical systems studied in this research program are shown below:

All chemical behavior involves movement of electrons. Chemical reactivity and catalysis depend on mechanisms that move electrons from existing bonds in starting materials to new bonds in desired products. Movement of electrons in materials is important to electrical conductivity and optical properties for technological applications. In biology, electron transfer involving active metal sites is central to many life processes. This research provides fundamental information for understanding all of these processes - the clues for solving the many mysteries of electron behavior in chemistry.

We are particularly interested in the study of molecules with unusual electronic structure and bonding modes. These molecules offer opportunities for unique properties and new applications. For instance, our discovery of the only molecule that requires less energy to give up an electron than any atom in the periodic table opens a new realm of behavior with many potential applications. The figure below shows the structure of this molecule. The two gold-colored atoms in the center are tungsten atoms, the blue atoms are nitrogens, and the rest is hydrocarbon.

We have developed instrumentation for gas-phase photoelectron spectroscopy of large molecules that is not matched elsewhere. It is the only instrumentation capable of measuring the ionization energies of many important molecules, including the one pictured. As a consequence, we are often the only source of this information for other researchers. In order to serve the needs for this information, we have established a user facility for gas-phase electron spectroscopy directed by Dr. Nadine Gruhn. We have numerous rewarding collaborations and often share students with other research groups, both within this Department and in other institutions.

Selected Publications

• Harb, Mohammad K.; Niksch, Tobias; Windhager, Jochen; Görls, Helmar; Holze, Rudolf; Lockett, L. Tori; Okumura, Noriko; Evans, Dennis H.; Glass, Richard S.; Lichtenberger, Dennis L.; El-khateeb, Mohammad; Weigand, Wolfgang. “Synthesis and Characterization of Diiron Diselenato Complexes Including Iron Hydrogenase Models.” Organometallics 2009, 28 (4), 1039–1048. (http://dx.doi.org/10.1021/om800748p)

• Chen, Shentan; Chisholm, Malcolm H.; Davidson, Ernest R.; English, Jason B.; Lichtenberger, Dennis L. “Theoretical and Spectroscopic Investigations of the Bonding and Reactivity of (RO)3M≡N Molecules, where M = Cr, Mo, and W.” Inorg. Chem. 2009, 48 (3), 828–837 (chosen for the cover article). (http://dx.doi.org/10.1021/ic801786u)

• Cranswick, Matthew A.; Gruhn, Nadine E.; Enemark, John H.; Lichtenberger, Dennis L. “Electronic Structure of the d1 Bent-metallocene Cp2VCl2: A Photoelectron and Density Functional Study.” Journal of Organometallic Chemistry 2008, 693, 1621-1627.

• Lobanova Griffith, Olga; Gruhn, Nadine E.; Anthony, John E.; Purushothaman, Balaji; Lichtenberger, Dennis L. “Electron Transfer Parameters of Triisopropylsilylethynyl-Substituted Oligoacenes.” J. Phys. Chem. C 2008, 112 (51), 20518–20524. (http://dx.doi.org/10.1021/jp8070629)

• Felton, Greg A. N.; Vannucci, Aaron K.; Okumura, Noriko; Lockett, L. Tori; Evans, Dennis H.; Glass, Richard S.; Lichtenberger, Dennis L. “Hydrogen Generation from Weak Acids: Electrochemical and Computational Studies in the [(η5-C5H5)Fe(CO)2]2 System.” Organometallics 2008, 27(18), 4671–4679. (http://dx.doi.org/10.1021/om800366h)

• Cozzolino, Anthony F.; Gruhn, Nadine E.; Lichtenberger, Dennis L.; Vargas-Baca, Ignacio. “Valence Electronic Structure of Benzo-2,1,3-chalcogenadiazoles Studied by Photoelectron Spectroscopy and Density Functional Theory.” Inorg. Chem. 2008, 47(14), 6220–6226. (http://dx.doi.org/10.1021/ic800055c)

• Durivage, Jason C.; Gruhn, Nadine E.; Li, Bo; Dikarev, Evgeny V.; Lichtenberger, Dennis L. ”The Electronic Structure and Bonding of the First p-Block Paddlewheel Complex, Bi2(trifluoroacetate)4, and Comparison to d-Block Transition Metal Paddlewheel Complexes: A Photoelectron and Density Functional Theory Study.” J. Cluster Science 2008, 19(1), 275-294. (http://dx.doi.org/10.1007/s10876-007-0179-9)

• Petro, Benjamin J.; Vannucci, Aaron K.; Lockett, L. Tori; Mebi, Charles; Kottani, Rudresha; Gruhn, Nadine E.; Nichol, Gary S.; Goodyer, Paul A. J.; Evans, Dennis H.; Glass, Richard S.; Lichtenberger, Dennis L. “Photoelectron spectroscopy of dithiolatodiironhexacarbonyl models for the active site of [Fe-Fe] hydrogenases: Insight into the reorganization energy of the "rotated" structure in the enzyme.” J. Mol. Struct. 2008, 890(1-3), 281-288. (http://dx.doi.org/10.1016/j.molstruc.2008.04.024)

• Cranswick, M.A.; Dawson, A.; Cooney, J.J.A.; Gruhn, N.E.; Lichtenberger, D.L. ; Enemark, J.H. “Photoelectron Spectroscopy and Electronic Structure Calculations of d1 Vanadocene Compounds with Chelated Dithiolate Ligands: Implications for Pyranopterin Mo/W Enzymes.” Inorg. Chem. 2007, 46, 10639-10646.

• Felton, G. A. N.; Vannucci, A.K.; Chen, J.; Moser, T.; Okumura, N.; Petro, B.J.; Zakai, U.I.; Evans, D.H.; Glass, R.H.; Lichtenberger, D.L. “Hydrogen Generation from Weak Acids: Electrochemical and Computational Studies of a Diiron Hydrogenase Mimic.” J. Am. Chem. Soc. 2007, 129(41), 12521-12530.

• Rajapakshe, A.; Basta, R.; Arif, A.M.; Ernst, R.D.; Lichtenberger, D.L. “Silyl Substitution Effects on Metal-Pentadienyl Bonding: Synthesis, Structure, Photoelectron Spectroscopy and Electronic Structure of a High Valent Half-Open Zirconocene.” Organometallics 2007, 26(11), 2867-2871.

• Joshi, H. K.; Cooney, J. A.; Inscore, F. E.; Gruhn, N. E.; Lichtenberger, D. L.; Enemark, J. H. "Investigation of Metal-Dithiolate Fold Angle Effects by Gas-Phase Photoelectron Spectroscopy and Density Functional Calculations: Implications for Molybdenum Enzymes." Proc. Natl. Acad. Sci. U.S.A. 2003, 100 (7), 3719-3724.

• Lichtenberger, D. "The Electron Distribution, Bonding, and J(Si-H) NMR Coupling Constant in (η⁵-C₅H₅)(CO)₂MnHSiCl₃: The Molecular Orbital View." Organometallics 2003, 22 (8), 1599-1602.

• Lichtenberger, D. L.; Fan, H. -J.; Gruhn, N. E. "Ligand-Mediated Metal-Metal Interactions and Localized versus Delocalized Mixed-Valence Cation States of Biferrocene and Bis(µ-fulvalenediyl)diiron Characterized in the Gas Phase by Valence Photoelectron Spectroscopy." J. Organomet. Chem. 2003, 666, 75-85.

• Cotton, F. A.; Gruhn, N. E.; Gu, J.; Huang, P.; Lichtenberger, D. L.; Murrillo, C. A.; Van Dorn, L. O.; Wilkinson, C. C. "Closed-Shell Molecules that Ionize More Readily than Cesium." Science 2002, 298, 1971-1974.

• Amashukeli, X.; Winkler, J. R.; Gray, H. B.; Gruhn, N. E.; Lichtenberger, D. L. "Electron-Transfer Reorganization Energies of Isolated Organic Molecules." J. Phys. Chem. 2002, 106, 7593-7598.

• Lichtenberger, D. L.; Gruhn, N. E.; Rai-Chaudhuri, A.; Renshaw, S. K.; Gladysz, J. A.; Jiao, H.; Seyler, J.; Igau, A. "Vibrational Progressions in the Valence Ionizations of Transition Metal Hydrides: Evaluation of Metal-Hydride Bonding and Vibrations in (η⁵-C₅R₅)Re(NO)(CO)H [R = H, CH₃]." J. Am. Chem. Soc. 2002, 124, 1417-1423.

• Westcott, B. L.; Gruhn, N. E.; Michelsen, L. J.; Lichtenberger, D. L. "Experimental Observation of Non-Aufbau Behavior: The Photoelectron Spectrum of Vanadyloctaethylporphyrinate and Vanadylphthalocyanine." J. Am. Chem. Soc. 2000, 122, 8083-8084.