Photodissociation Dynamics of Chloroiodomethane in Acetonitrile Studied by Ultrafast Pump-Probe Spectroscopy

We have studied the photodissociation dynamics of chloroiodomethane (CH2ICl) in acetonitrile by ultrafast pump‐probe spectroscopy. The reaction was initiated using a femtosecond pulse at 266 nm and the transient absorption was measured out to delays of 300 ps over a spectral region from 330 to 850 nm. The photodissociation leads to formation and subsequent vibrational cooling of a product species, which we suggest is the isomer of chloroiodomethane, CH2Cl‐I, likely produced via in‐cage recombination between the nascent fragments CH2Cl and I.