PIER Photon Science Colloquium: Coherent Ultrafast Multi-dimensional Spectroscopy of Molecules; from NMR to X-rays
by
Prof.Shaul Mukamel(Dept. of Chemistry, University of California, Irvine, USA)
→
Europe/Berlin
Bldg 28c, Seminar Room
Bldg 28c, Seminar Room
Description
Multidimensional techniques which originated with NMR and extended to the visible regime apply sequences of femtosecond pulses to reveal detailed structural and dynamical molecular information through correlation plots.
Elementary energy-transfer and charge-separation pathways in chromophore aggregates may be probed by sequences of visible, UV and X-ray pulses. This will be demonstrated for the bacterial photosynthetic reaction center and for semiconductor quantum dots. Two dimensional signals that make use of the quantum nature of light (entangled photons) by varying the parameters of the photon wave function will be presented.
Extensions of these ideas the x-ray regime will allow to employ sequences of attosecond x-ray pulses in order to probe electronic and nuclear dynamics in molecules. Applications will be presented to the stimulated x-ray Raman spectra of trans-N-methylacetamide and Cysteine at the Nitrogen, Sulfur and the Oxygen K-edges. The signals are interpreted in terms of the dynamics of valence electronic wave packets prepared and detected in the vicinity of a selected atom. By creating multiple core holes at controlled times it is possible to study the dynamics and correlations of valence electrons as they respond to these perturbations.
