Dr. Marius Wanko


marius [dot] wanko [at] gmail [dot] com
(+34) 943 01 8393
(+34) 943 01 83 90

Research Information

Research Overview

Photoinduced Processes in Biologic Systems

Novel ultrafast experimental techniques, like the femtosecond pump-probe spectroscopy, provide access to the time-scale of photochemical reactions. The data obtained in these experiments, however, are difficult to interpret in terms of the evolution of the electronic and nuclear structure. The theoretical simulation of these processes can provide the missing information and test different conceptional models. In combination, theory and experiment can achieve a new understanding of many photoinduced processes that are of high scientific or technologic interest:

  • Photoisomerization of the retinal chromophore. This triggers
    the photocyle of rhodopsins and other G-protein coupled receptors and is the first step in the vision process as well as the light harvesting of archae bacteria (DFG-FG490).
  • Photoizomerization and excited-state proton transfer determine the fluorescence properties of fluorescent proteins like GFP, YFP, CFP, RFP. Derived from the green-fluorescent protein (GFP) of the jellyfish Aequorea victoria, these proteins have been modified by genetical engineering and are heavily used as fluorescent tags in molecular biology.
  • Ultrafast decay of photo-excited biologic molecules is an essential property to prevent damange by visible and UV light.
  • Effective photoabsorption and ultrafast charge transfer are prerequisites for the functioning of organic photovoltaic cells.

Ultrafast Photochemistry of Organic Chromophores

The simulation of the non-adiabatic excited-state dynamics represents a great methodological challange for quantum-chemical approaches. The correct and accurate description of the potential energy surfaces of different electronic states is required to predict a realistic dynamics that can be compared with experimental data. The testing of these methods and analysis of their problems and limitations are therefore essential for successful and reliable applications.

Theoretical Spectroscopy on Biomolecules

The initial (or ground) state of proteins can be resolved at near-atomic resolution using x-ray crystallography. The complex structural and chemical changes that the protein undergoes during its action can be investigated experimentally by time-resolved spectroscopy, or spectroscopy on frozen intermediates. These spectroscopic techniques (IR, UV/VIS, Raman, NMR, etc.) can detect structural changes in specific moleclar groups and hydrogen bonded networks and the time-scale at which they occur. However, it is difficult to assing and interpret these changes to individual parts and fragments of the protein and to connect the structural information with the function or dynamics of the system. Theoretical spectroscopy can help to validate atomistic models of the initial and intermediate states, assumptions over protonation states and test concepts of structure-function relationship.

Related Research Areas

Latest publications

Electronic band gaps of confined linear carbon chains ranging from polyyne to carbyne
Lei Shi, Philip Rohringer, Marius Wanko, Angel Rubio, Sören Waßerroth, Stephanie Reich, Sofie Cambré, Wim Wenseleers, Paola Ayala, Thomas Pichler
Physical Review B 1, 075601 (2017)
Confined linear carbon chains as a route to bulk carbyne
L. Shi, P. Rohringer, K. Suenaga, Y. Niimi, J. Kotakoski, J.C. Meyer, H. Peterlik, M. Wanko, S. Cahangirov, A. Rubio, Z.J. Lapin, L. Novotny, P. Ayala, T. Pichler
Nature Materials 15, 634 - 639 (2016)