Photochemistry and Spectroscopy Department

Institute of Physical Chemistry, Polish Academy of Sciences

 


Group 29: Photophysics and spectroscopy of photoactive systems: structure and reactivity of systems with hydrogen bonds

 

Head of the group: Jacek Waluk

 

Members

 

Current projects

 

 

Our research encompasses various aspects of physical organic chemistry. A subject of particular interest is proton/hydrogen transfer, intramolecular as well as intermolecular, occurring in the ground and excited electronic states. Since proton transfer characteristics are closely related to the properties of hydrogen bond between the donor and acceptor moieties, we study geometry, electronic, and vibrational structure of various H-bonded molecules and molecular complexes, including bifunctional HB donor/acceptor systems. Among those, porphycenes are role models for the double intramolecular hydrogen transfer, whereas the intermolecular reactions are investigated for derivatives of indole, pyrrole, carbazole, pyridine, quinoline, often with H-bond donor acceptor moieties linked by a single bond.

 

We also study photoinduced electron transfer, often accompanied by conformational changes, as well as photochromic processes, resulting in complex interplay between tautomerism and rotational isomerism. We recently described photoinduced electron/proton transfer coupled with twisting.

 

Much work is devoted to synthesis, spectroscopy, and photophysics of porphyrin isomers, porphycenes in particular. These chromophores are studied on the level of single molecules using fluorescence and Raman techniques. The regime of molecular isolation is achieved by supersonic jets and matrix isolation methods. These procedures have led to the discovery of vibrationalmode-selective tunneling splittings in porphycenes. Time-resolved studies in condensed phases are carried out using transient absorption and emission techniques.

 

Different methodologies of spectroscopy with polarized light are being developed, enabling, i.a., determination of ultrafast reaction rates (in particular for a special case of self-exchange reactions) or monitoring tautomerism in single molecules.

 

We are currently extending studies of photoinduced processes to plasmonic environments.

 

Our experiments are supplemented by quantum chemical and molecular dynamics calculations.