REACTION PATHWAYS IN THE PHOTODETACHMENT OF AN ELECTRON FROM AQUEOUS CHLORIDE : A QUANTUM MOLECULAR DYNAMICS STUDY

摘要: Reaction and relaxation processes induced by photoexcitation of an aqueous chloride ion are studied with quantum molecular dynamics simulations. A predominant channel leading to a metastable hydrated electron‐chlorine pair is found. By means theoretical transient stationary absorption spectra, the solvent reorganization involved in charge repartitioning discussed. The dissipation excess electron kinetic energy surrounding water molecules plays essential role equilibration electron‐atom pair. For this intermediate species, two competing reaction pathways identified. One barrier‐impeded dissociation yielding electron. Shape height free barrier determined umbrella sampling point diffusion controlled photodetachment. other geminate recombination via nonadiabatic transition for which self‐consistent fully dynamical treatment electronic polarization found be important. From rate constants computed individual channels, model derived explain time‐dependent spectral signatures escape yields recently observed photodetachment experiments on halides.