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 CH3I+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 I2 formation. Direct clocking of the CH3I dissociation, hitherto unobserved, gives 150 fs for the C–I bond breakage time and 0.8 Å for the repulsion length scale.