Observation of the solvent shell reorganization around photoexcited atomic solutes by picosecond X-ray absorption spectroscopy

We report on the observation of the solvation shell rearrangement after abstraction of the electron from aqueous I- in a laser pump/X-ray probe experiment by recording the X-ray absorption L-1- and L-3-edge spectra, 50 ps after laser excitation. The L-1-edge spectra clearly identify the I-0 neutral species after excitation and suggest a substantial amount of back-transfer of charge from the solvent species. Both edge spectra point to a significant rearrangement of the solvation shell around I-0.