Research

In particular, femtosecond nonlinear spectroscopy in the ultraviolet, the visible, and the infrared spectral regions are used to exploit the time-dependent molecular-optical properties that are associated with chemical transformations. We are interested in reactive processes such as light-triggered dissociations, proton and electron transfer reactions, and conformational isomerizations. In addition, we explore non-reactive dynamics such as intermolecular vibrational energy transfer, intramolecular vibrational redistribution, electronic dephasing and time-dependent solvation.

To this end, we implement in our laboratories novel techniques of femtosecond electronic and vibrational spectroscopies such as rapid-scan time and frequency-resolved transient absorption, fluorescence upconversion, IR and VIS photon echoes, Raman-induced optical Kerr effect and femtosecond multidimensional infrared spectroscopy (2DIR). Such tools are being supplemented by single-molecule methods like confocal fluorescence lifetime imaging and fluorescence correlation spectroscopy.

We are particularly interested in observing chemical dynamics in hydrogen-bonded systems and in disclosing the influence of hydrogen-bonding on chemical reactivity. The hydrogen-bonded systems we focus on range from simple molecular liquids such as water and aqueous solutions to highly complex supramolecular architectures. Hydrogen-bonded liquids are studied under a wide variety of thermodynamic conditions ranging from nanoscopic liquid droplets with interfaces to soft matter, to bulk liquid and supercritical phases at elevated pressures and temperatures. Supramolecular hydrogen-bonded architectures are being fabricated artificially by our synthetically oriented project partners using advanced methods of organic and inorganic synthesis.