Ultrafast x-ray spectroscopy for structural dynamics studies in chemistry and biology

Time-resolved x-ray absorption fine structure (XAFS) spectroscopy with picosecond temporal resoln. is a new method to observe electronic and geometric structures of short-lived reaction intermediates. It combines an intense femtosecond laser source synchronized to the x-ray pulses delivered into the microXAS beamline of the Swiss Light Source (SLS). We present key expts. on charge transfer reactions as well as spin-crossover processes in coordination chem. compds. next to solvation dynamics studies of photogenerated at. radicals.