Research

In the visible, ultraviolet up to the vacuum-ultraviolet spectral range electronic excitations determine the optical properties of molecules and solid materials. These excitations are directly linked to the structure and chemical bonding. Thus, spectra in the VIS-VUV-range have fingerprint character for the atomic structure of molecules, molecule layers and interfaces. The broad spectral range extending far into the VUV is realized using synchrotron radiation at BESSY II. ISAS Berlin is operating a synchrotron ellipsometer at BESSY in the spectral range of 2.5 eV (500 nm) to 35 eV (34 nm) in cooperation with 16 research groups.
Of particular interest to our research are molecule-solid interfaces, nanostructures down to submonolayer coverage and wide band gap materials. The complex relation between optical properties and atomic structure serves for a broad basis of analytic information. The link between optical spectra and atomic structure is investigated in a close collaboration with theory groups by studying some molecule terminated prototype surfaces.