Research

The Sokolowski group investigates the chemical bonding of large organic molecules to surfaces of solids. In particular, pi-conjugated molecules are of interest, which are also utilized in organic semiconductor devices (OLEDs and OFETs). These molecules are interesting due to their electronic excitations on the pi system, their structural internal degrees of freedom, and the formation of stable films.

The focus is on the following topics:

The structure of the adsorption complex, i.e. the identification and understanding of the exact geometric structure of the molecule after adsorption on the surface. Combined with theoretical calculations, exact conclusions about the nature of the chemical bond between the solid surface and the molecule can be drawn. More recently, the focus has shifted from the adsorption on metallic surfaces towards to that on insulator surfaces.

Optical properties of isolated or aggregated molecules on surfaces. Here, measurements by fluorescence spectroscopy are of interest. These can be performed with very high spectral resolution and allow both the spectroscopy of isolated (individual) molecules as well as ordered molecular assemblies. The experiments concern the effect of the surface bonding as well as the surface-induced lateral arrangement of the molecules on the optical spectra. Finally, the group uses high resolution laser spectroscopy for measuring the spectra of single molecules on surfaces.