Research topics of the Domcke group related to the theory of radiation damage
Chair of Theoretical Chemistry, Department of Chemistry, Technical University of Munich, D-85747 Garching, GERMANY
Tel.: +49 89 289 13616 Fax: +49 89 289 13622
A. Ab initio exploration of excited-state potential-energy surfaces and photochemical reaction paths of molecules and clusters
Multi-reference electronic-structure methods are employed to explore reaction pathways, potential-energy functions and conical intersections in chromophores of biological interest. We are interested, in particular, in the elementary mechanisms of the photochemistry of aromatic amino acids (tryptophan and tyrosine) and the DNA and RNA bases. In addition to the isolated biomolecules, their complexes with each other (base pairs) as well as with typical solvent molecules (such as water) also are investigated. We try to identify the photoreactive electronic states and the reaction paths leading to conical intersections with the electronic ground state. There is increasing consensus that the latter lead to ultrafast radiationless deactivation of the photoexcited states, which is essential for the photostability of the building blocks of life.
Selected publication: A. L. Sobolewski, W. Domcke, C. Dedonder-Lardeux and C. Jouvet, Phys. Chem. Chem. Phys. 4, 1093 (2002).
B. Dynamics at conical intersections of electronic potential-energy surfaces: femtochemistry
Time-dependent quantum wave-packet and reduced density-matrix methods are developed and applied to the analysis of specific features of the ultrafast dynamics at conical intersections. For suitably selected model systems, such as pyrrole, indole or phenol, we try to develop a quantitative microscopic description of the ultrafast excited-state deactivation processes on multiple electronic potential-energy surfaces. Observables of interest are the time-dependent electronic population probabilities (after initial preparation of the excited state) , the coherence and energy transfer of vibrational modes, and reaction probabilities for photodissociation.
Selected publication: W. Domcke and G. Stock, Adv. Chem. Phys. 100, 1 (1997).
C. Theory of femtosecond time-resolved nonlinear spectroscopy
Methods are developed for the calculation of general four-wave mixing spectra as well as for time-gated fluorescence spectra and time-resolved photoelectron spectra, with emphasis on the ultrafast nonadiabatic dynamics of organic chromophores. The goal is the quantitative simulation of femtosecond pump-probe spectra for complex systems such as amino acids and DNA bases.
Selected publication: A. V. Pisliakov, M. F. Gelin and W. Domcke, J. Phys. Chem. A 107, 2657 (2003).
COST P9 Workings group(s) of interest: