Quantum Bioinorganic Chemistry
We employ advanced theoretical methods to investigate metalloenzymes, focusing on elucidating the properties and catalytic function of transition metals and the role of redox-active residues or cofactors. In parallel, we are studying synthetic models to better understand how fundamental aspects of the electronic structure correlate with experimental observables. Our approach is emphasizing the development and application of methods for the calculation of magnetic and spectroscopic properties of transition metal systems with high nuclearity and electronic complexity. Particular emphasis is placed on electron paramagnetic resonance (EPR) properties. Among the methods developed in our group are spin projection techniques that allow calculation of experimentally comparable spectroscopic parameters for systems of arbitrary nuclearity from DFT calculations. In recent years we are pursuing new methodologies for the study of spectroscopic properties and magnetic exchange coupling interactions in polynuclear systems based on multireference methods. The new approaches emerging from this work hold great promise for the first-principles treatment of large and complex strongly correlated systems relevant to bioinorganic chemistry, molecular magnetism, and quantum computing.
Representative publications:
N.-A. Stamos, E. Ferentinos, M. Chrysina, C. P. Raptopoulou, V. Psycharis, Y. Sanakis, D. A. Pantazis, P. Kyritsis, G. Mitrikas (2020) Unusual 31P Hyperfine Strain Effects in a Conformationally Flexible Cu(II) Complex Revealed by Two-Dimensional Pulse EPR Spectroscopy, Inorg. Chem., 59, 3666-3676.
https://dx.doi.org/10.1021/acs.inorgchem.9b03237
C. J. Stein, D. A. Pantazis, V. Krewald (2019) Orbital Entanglement Analysis of Exchange-Coupled Systems, J. Phys. Chem. Lett., 10, 6762-6770
https://dx.doi.org/10.1021/acs.jpclett.9b02417
D. A. Pantazis (2019) Meeting the Challenge of Magnetic Coupling in a Triply-Bridged Chromium Dimer: Complementary Broken-Symmetry Density Functional Theory and Multireference Density Matrix Renormalization Group Perspectives, J. Chem. Theory Comput., 15, 938-948.
https://dx.doi.org/10.1021/acs.jctc.8b00969
D. A. Pantazis (2019) Assessment of Double-Hybrid Density Functional Theory for Magnetic Exchange Coupling in Manganese Complexes, Inorganics, 7, 57.
https://dx.doi.org/10.3390/inorganics7050057
Z. Mathe, D. A. Pantazis, H. B. Lee, R. Gnewkow, B. E. Van Kuiken, T. Agapie, S. DeBeer
(2019) Calcium Valence-to-Core X-ray Emission Spectroscopy: A Sensitive Probe of Oxo Protonation in Structural Models of the Oxygen-Evolving Complex, Inorg. Chem., 58, 16292-16301. (Cover Article)
https://dx.doi.org/10.1021/acs.inorgchem.9b02866
M. Roemelt, V. Krewald and D. A. Pantazis (2018) Exchange Coupling Interactions from the Density Matrix Renormalization Group and N-Electron Valence Perturbation Theory: Application to a Biomimetic Mixed-Valence Manganese Complex, J. Chem. Theory Comput., 14, 166-179.
https://dx.doi.org/10.1021/acs.jctc.7b01035
S. Paul, N. Cox, and D. A. Pantazis (2017) What can we learn from a biomimetic model of nature’s oxygen-evolving complex?, Inorg. Chem., 56, 3875-3888.
https://dx.doi.org/10.1021/acs.inorgchem.6b02777
K. M. E. Burton, D. A. Pantazis, R. G. Belli, R. McDonald, and L. Rosenberg (2016) Alkene insertions into a Ru-PR2 bond, Organometallics, 35, 3970–3980. (ACS Editor’s Choice)
https://dx.doi.org/10.1021/acs.organomet.6b00757
K. C. Christoforidis, D. A. Pantazis, L. L. Bonilla, E. Bletsa, M. Louloudi, and Y. Deligiannakis (2016) Axial ligand effect on the catalytic activity of biomimetic Fe-porphyrin catalyst: An experimental and DFT study, J. Catal., 344, 768-777.
https://dx.doi.org/10.1016/j.jcat.2016.08.013