Wave-packet dynamics of photoinduced hydrogen-transfer and hydrogendetachment process

• Antragsteller: Professor Dr. Wolfgang Domcke
• Fachliche Zuordnung: Theoretische Chemie: Elektronenstruktur, Dynamik, Simulation
• Förderung: Förderung von 2000 bis 2008
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 5281978

• Erstellungsjahr: 2007

Zusammenfassung der Projektergebnisse

The role of electron- and proton-transfer processes in the photophysics of hydrogen-bonded aromatic systems has been explored with ab initio electronic structure calculations and timedependent quantum wave-packet calculations. Photochemically reactive excited electronic states of 1(pi)σ* or 1(pi)(pi)* character have been characterized for pyrrole, phenol, adenine as well as for hydrogen-bonded aromatic pairs such as the guanine-cytosine and adenine-thymine DNA base pairs. A common feature of the photochemistry of these systems is the electrondriven proton-transfer mechanism: highly polar charge-transfer states drive the proton transfer, which leads to a conical intersection of the Si and So potential-energy surfaces and thus ultrafast deactivation of the excited electronic states. Computational methods have been developed which allow the simulation of these ultrafast and multi-dimensional reaction processes. The results shed light on the specific excited-state reaction mechanisms which are essential for the function of organic photostabilizers and the photostability of biological molecules.

Projektbezogene Publikationen (Auswahl)

• V. Vallet, Z. Lan, S. Mahapatra, A.L. Sobolewski and W. Domcke, Time-dependent quantum wave-packet description of the 1(pi)σ* photochemistry of pyrrole, Faraday Discuss. 127, 283 (2004).
  
  
• V. Vallet, Z. Lan, S. Mahapatra, A.L. Sobolewski and W. Domcke, Photochemistry of pyrrole : time-dependent quantum wave-packet description of the dynamics of the 1(pi)σ* - S0 conical intersections, J. Chem. Phys. 123, 144307 (2005).
  
  
• A.L. Sobolewski and W. Domcke, Ab initio studies on the photophysics of the guanine-cytosine base pair, PCCP 6, 2763 (2004).
  
  
• A.L. Sobolewski and W. Domcke, Ab initio study of the excited-state coupled electron-proton-transfer process in the 2-aminopyridine dinier, Chem. Phys. 294, 73 (2003).
  
  
• A.L. Sobolewski and W. Domcke, Computational studies of the photophysics of hydrogen-bonded molecular systems, J. Phys. Chem. A 111, 11725 (2007).
  
  
• A.L. Sobolewski and W. Domcke, Conical intersections induced by repulsive mr* states in planar organic molecules: malonaldehyde, pyrrole and chlorobenzene as photochemical model systems, Chem. Phys. 259, 181 (2000).
  
  
• A.L. Sobolewski and W. Domcke, Intramolecular hydrogen bonding in the SI(TUI*) excited state of anthranilic acid and salicylic acid: TDDFT calculation of excited-state geometries and infrared spectra, J. Phys. Chem. A 108, 10917 (2004).
  
  
• A.L. Sobolewski and W. Domcke, Photoinduced electron and proton transfer in phenol and its clusters with water and ammonia, J. Phys. Chem. A 105, 9275 (2001).
  
  
• A.L. Sobolewski and W. Domcke, The chemical physics of the photostability of life, Europhysicsnews 37, 20 (2006).
  
  
• A.L. Sobolewski, W. Domcke and C. Hättig, Tautomeric selectivity of the excitedstate lifetime of guanine/cytosine base pairs: the role of electron-driven proton-transfer processes, Proc. Natl. Acad. Sei. USA 102, 17903 (2005).
  
  
• A.L. Sobolewski, W. Domcke, C. Dedonder-Lardeux and C. Jouvet, Excited-state hydrogen detachment and hydrogen transfer driven by repulsive 'TNT* states: a new paradigm for nonradiative decay in aromatic biomolecules, PCCP 4, 1093 (2002).
  
  
• L.M. Frutos, A. Markmann, A.L. Sobolewski and W. Domcke, Photoinduced electron and proton transfer in the hydrogen-bonded pyridine-pyrrole system, J. Phys. Chem. B 111,6110 (2007).
  
  
• S. Perun, A.L. Sobolewski and W. Domcke, Photostability of 9H-adenine: mechanisms of the radiationless deactivation of the lowest excited singlet states, Chem. Phys. 313,107 (2005).
  
  
• S. Perun, A.L. Sobolewski and W. Domcke, Role of electron-driven proton-transfer processes in the excited-state deactivation of the adenine-thymine base pair, J. Phys. Chem. A 110, 9031 (2006).
  
  
• T. Schultz, E. Samoylova, W. Radloff, I.V. Hertel, A.L. Sobolewski and W. Domcke, Efficient deactivation of a model base pair via excited-state hydrogen transfer, Science 306,1765(2004).
  
  
• Z. Lan, A. Dupays, V. Vallet, S. Mahapatra and W. Domcke, Photoinduced multimode quantum dynamics of pyrrole at the 'TIG* - So conical intersections, J. Photochem. Photobiol. A 190, 177 (2007).
  
  
• Z. Lan, W. Domcke, V. Vallet, A.L. Sobolewski and S. Mahapatra, Time-dependent quantum wave-packet description of the 'na* photochemistry of phenol, J. Chem. Phys. 122,224315 (2005).