Lehrstuhl für Physikalische Chemie II
Am Hubland, 97074/Würzburg
Research foci (and basic equipment-based research projects):
Besides linear Raman techniques (linear: linear correlation between the induced dipolemoment and the electric field strength) also various non-linear (non-linear: induced polarization is proportional to a higher power of the incoming electric field or to the product of several light fields ) methods are applied in this project for structural and dynamical investigations of molecules and solids. Especially so called four-wave mixing techniques where three laser beams interact with the sample to produce the signal are used in this project. Coherent anti-Stokes Raman scattering (CARS) is a special form of four-wave mixing and yields as indicated by the name Raman information. With the aid of CARS spectroscopy under variable electronic resonance conditions structural information about the macrocycle of various substituted porphyrines could be obtained. Since porphyrines are highly fluorescent molecules linear Raman techniques could not provide such information. Furthermore transient molecular states have been investigated by means of ns time-resolved CARS spectroscopy. By doing so the reaction is started by a ns UV-laser pulse and the resulting transient species are investigated for various time delays by recording CARS spectra which yield information about the ro/vibrational levels of the transient species as a function of the delay time between the UV excitation and the CARS process.
For the results in this research area, please consult the above-mentioned publications.
Rewards and prizes:
Prof. Dr. W. Kiefer: Honorary Fellow of the Laser and Spectroscopy Society of India (F.L.S.S.), 1999. - Distinguished Service Award of the Society of Applied Spectroscopy, 2000. - Foreign Councillor of the Institute for Molecular Science, Okazaki National Research Institutes, Okazaki, Japan, 1999-2001. - Technical Expert Monitor of the International Science and Technology Center, Moscow, Russia, 1999-2002. - Chief Editor of the: Journal of Raman Spectroscopy, 2000.-- PD Dr. J. Popp: Zehetmaier Award (postdoctoral lecture qualification scholarship) awarded by the Freistaat Bayern, 1999. - Cooperation Prize of the University of Würzburg, 2001, - Bunsen-Kirchhoff Prize awarded by the German Bunsen-Society, 2002. -- PD Dr. A. Materny: Heisenberg-Scholarship, 1999. -- Dr. Sebastian Schlücker: VCI Graduate Research Fellowship, 1999. - Mathias-Manger Award (Diploma) of the Faculty of Chemistry and Pharmacy, 1999. - Faculty Award (Dissertation) of the Faculty of Chemistry and Pharmacy, 2002.
Universal non-linear Raman set up: nanosecond Nd:YAG laser pumped dye laser system / Spex 1404 double monochromator / CCD camera / accessories.