MAGNETIC-FIELD EFFECT ON PICOSECOND ELECTRON-TRANSFER

The recombination dynamics of a transition metal redox system monitore d by femtosecond pump-probe spectroscopy are shown to be sensitive to high magnetic fields at times shorter than 10 picoseconds. The effect, based on coherent population beats of different spin states, is quant itatively accounted for and allows direct access to spin relaxation ra tes far beyond the time resolution of the fastest electron paramagneti c resonance technique. The presence of this ultrafast magnetic field e ffect helps in understanding complex reaction schemes in transition me tal chemistry, which occur in a wide range of fields, such as bioinorg anic chemistry and catalysis.