X-rays have as ionizing radiation a number of unique properties beyond their very short wavelength. One important property for our science is their element selectivity. By choosing and investigating the spectra of particular elements that are placed at unique places in complex molecules we have a localized "atomic sensor". By investigating these atoms at different times after a molecule was excited with light we can trace the development of electronic and structural changes even in very complex systems or in other words follow the electron through the molecule and over interfaces.

With the combination of the complementary information obtained with time-resolved X-ray absorption, X-ray emission and X-ray scattering we have successfully traced the electron transfer in complex molecules like the shown Ruthenium - Platinum or Ruthenium - Cobalt complexs with very high time-resolution. We are investigating novel iron-carbene complexes for solar light sensitization, light activated catalysts, novel polymer structures combining light sensitization and catalytic properties and novel nano dots for light sensitization and catalysis.