Dr. Brünig completed his doctoral research in October 2023 under the supervision of Professor Roland R. Netz in the "Theory of Structure and Kinetics of Biological Soft-Matter Systems" research group at the Freie Universität Berlin. His work was part of the Integrated Graduate School within the Collaborative Research Center (SFB) 1078, which focused on "Protonation Dynamics in Protein Function." The thesis, titled "Non-Markovian Dynamics and Vibrational Spectroscopy of Hydrated Protons and Water", earned the highest distinction, summa cum laude.

The dissertation explores the intricate dynamics of proton transfer in water and its spectroscopic signatures, combining theoretical modeling with experimental collaborations. Dr. Brünig worked closely with Professors Karsten Heyne (SFB project B7), Hartmut Oschkinat (SFB project B1), and Igor Schapiro (SFB project C6), contributing to several significant publications, including articles in Nature Communications and the Journal of Chemical Physics, which were part of his cumulative dissertation.

Insights from the Dissertation

One of the highlights of Dr. Brünig's research was the development of analytical models for proton transfer dynamics. His work provided a deeper understanding of the vibrational and infrared spectral signatures associated with proton movement, such as in hydrochloric acid solutions. Notably, his study published in Nature Communications demonstrated how infrared spectroscopy reveals the proton-transfer processes fundamental to the Grotthuss mechanism.

Another publication in the Journal of Chemical Physics expanded on these findings, introducing trajectory-decomposition techniques that go beyond traditional normal-mode analysis. This approach illuminated the role of free-energy barriers in proton transfer and identified two distinct timescales that influence the absorption spectrum — broad waiting times and rapid transfer events — with implications for both experimental and theoretical research.

List of all publications:

1. Brünig, F.N., Hillmann, P., Kim, W.K., Daldrop, J.O. and Netz, R.R. (2022). Proton-transfer spectroscopy beyond the normal-mode scenario. J Chem Phys, 157, 17: 174116 doi: http://dx.doi.org/10.1063/5.0116686
2. Brünig, F.N., Rammler, M., Adams, E.M., Havenith, M. and Netz, R.R. (2022). Spectral signatures of excess-proton waiting and transfer-path dynamics in aqueous hydrochloric acid solutions. Nat Commun, 13, 1: 12 doi: http://dx.doi.org/10.1038/s41467-022-31700-x
3. Brünig, F.N., Geburtig, O., von Canal, A., Kappler, J. and Netz, R.R. (2022). Time-Dependent Friction Effects on Vibrational Infrared Frequencies and Line Shapes of Liquid Water. J Phys Chem B, 126, 7: 1579-1589 doi: http://dx.doi.org/10.1021/acs.jpcb.1c09481
4. Brünig, F.N., Netz, R.R. and Kappler, J. (2022). Barrier-crossing times for different non-Markovian friction in well and barrier: A numerical study. Phys Rev E, 106, 4: 20 doi: http://dx.doi.org/10.1103/PhysRevE.106.044133
5. Brünig, F.N., Daldrop, J.O. and Netz, R.R. (2022). Pair-Reaction Dynamics in Water: Competition of Memory, Potential Shape, and Inertial Effects. J Phys Chem B, 126, 49: 10295-10304 doi: http://dx.doi.org/10.1021/acs.jpcb.2c05923

Legacy of the Award

The PGzB Dissertation Award, is sponsored by SPECS GmbH since 2015 and continues to celebrate excellence in physics research conducted at universities in Berlin and Brandenburg. The Physikalische Gesellschaft zu Berlin e.V. is the regional association of Berlin/Brandenburg of the Deutsche Physikalische Gesellschaft e.V.

Dr. Brünig’s exceptional contributions to the understanding of proton dynamics not only deepen our fundamental knowledge of physical chemistry but also set a benchmark for interdisciplinary research bridging physics, chemistry, and biology.

Congratulations Florian!