Fachbereich Physik - Institut für Experimentalphysik

Who We Are

The Horch research group ‘Ultrafast Dynamics in Catalysis’ aims to understand complex catalytic systems and superordinate reaction networks by using an integrated approach of advanced spectroscopic and theoretical methods. In particular, we are interested in metalloenzymes – huge metal-containing proteins that catalyze, e.g., the conversion of small molecules like hydrogen and carbon dioxide. On the one hand, these complex biological machines are key to cellular energy metabolism.

On the other hand, their unrivalled efficiency and specificity make them valuable targets for biotechnological applications and bio-inspired catalyst design – given that their mechanistic features are properly understood. Thus, we utilize time-resolved, multidimensional, and computational spectroscopy to explore the structure, function, and dynamics of these fascinating biocatalysts in detail.

More details about the Horch research group can be found here:

We offer a PhD position in the project ‘Understanding Metalloenzymes by Computational Nonlinear Infrared Spectroscopy – Insights into the Structure, Function, and Dynamics of Hydrogenases’.

[NiFe] hydrogenases catalyze the reversible cleavage of hydrogen at a protein-embedded nickel-iron center containing biologically unusual carbon-monoxide and cyanide ligands. Due to these unique features and the potential of hydrogen as a clean fuel, these metalloenzymes are of major interest. Utilizing the carbon-monoxide and cyanide ligands as site-elective and structurally sensitive infrared (IR) probes, IR spectroscopy has long been used as a key technique for studying hydrogenases.

To overcome inherent limitations of conventional IR absorption experiments, we have introduced ultrafast and two-dimensional (2D) IR techniques into hydrogenase research. To exploit these nonlinear IR techniques to their full potential, computational strategies for simulating 2D-IR spectra of [NiFe] hydrogenases should be established and applied. In this respect, quantum chemical methods and molecular dynamics simulations will be utilized. The project is supposed to (1) yield an understanding of nonlinear IR spectra of hydrogenases and the encoded structural and dynamical properties, (2) provide a general computational toolbox for studying these aspects in metalloenzymes, and (3) draw a clear picture of the catalytic mechanism of hydrogenases that also integrates theoretical aspects beyond spectroscopic observables.

• Quantum chemical calculations (using mainly DFT) and hybrid QM/MM calculations
• Classical, ab initio, and QM/MM dynamics simulations
• Design of computational models of the catalytic nickel-iron center and its protein environment
• Detailed analysis of structural aspects, potential energy surfaces, and bond properties
• Prediction of static and dynamic observables of 2D-IR spectra, e.g. transition energies (using vibrational perturbation theory, GVPT2) and spectral diffusion (using MD simulations)
• If feasible, involvement in selected spectroscopic experiments
• Writing of scientific articles for publication in international peer-reviewed journals
• Presentation of research results at international scientific conferences

Master’s degree (or equivalent) in physical / theoretical chemistry, (chemical / bio) physics, or a related field.

• Excellent university degree
• Experience with quantum chemical methods and/or molecular dynamics simulations (see above)
• Experience with nonlinear and/or vibrational spectroscopy
• Knowledge in biological and/or inorganic chemistry
• Programming skills, preferably in Python
• Ability to work independently and as part of an interdisciplinary team
• Creativity, enthusiasm, and a genuine interest in the…