Bimolecular reactions observed by femtosecond detachment to aligned transition states: Inelastic and reactive dynamics

With fs radical detachment and kinetic energy‐resolved time‐of‐flight (KETOF) mass spectrometry, we are able to study the transition state dynamics of the bimolecular reaction CH_3I+I, inelastic and reactive channels; the collision complex is coherently formed (1.4 ps) and is long lived (1.7 ps). We also report studies of the dynamics of I_2 formation. Direct clocking of the CH_3I dissociation, hitherto unobserved, gives 150 fs for the C–I bond breakage time and 0.8 Å for the repulsion length scale.