Femtosecond experiments and absolute rate calculations on intervalence electron transfer of mixed-valence compounds

Abstract

New experimental results and theoretical calculations are reported for the optical electron transfer (ET) and subsequent reverse radiationless ET for the molecules (NH₃)₅Ru^IIINCRu^II(CN)⁻₅ and (NH₃)₅Fe^IIINCRu^II(CN)⁻₅. A procedure is presented for extracting many of the key parameters in ET theory from a combined analysis of resonance Raman data and the optical absorption ET band shape. Using these parameters, ET rates have been calculated using contemporary ET models. The experimental and theoretical rates agree within the uncertainty of the theoretical predictions, which results from an uncertainty in some of the parameters. The results demonstrate that inertial solute/solvent interactions and intramolecular sources of fast energy fluctuations play an important role in ultrafast ET kinetics for these compounds.