Prompt solvent-induced electronic predissociation of femtosecond pumped iodine. A computational study

Solvent-induced electronic predissociation (X → B → alg(3Π) state) of molecular iodine is discussed using a classical ensemble representation of Heisenbergʹs equations of motion. Excitation of the intermediate B state by an ultrafast pulse creates a coherent vibrational motion in this bound state. The localized solvent-induced coupling to the a state results in the spawning of dissociation products which occurs in bursts, twice per vibrational period. Equations of motion for both the electronic and nuclear degrees of freedom in each electronic state are derived from a quantum mechanical Hamiltonian. These equations are coupled whenever two electronic states are interacting. The formalism includes coupling to the sorrounding classical solvent. Comparison with a pump-probe experiment is provided.