Photo-induced ion transfer across the liquid/liquid interface

Traditional studies of ion transfer across the interface between two immiscible liquids involve the establishment of a steady-state ion current across the interface. The data obtained from these studies are used to develop models of the interfacial kinetic. However, this approach, while straightforward to implement experimentally, is not sensitive to the microscopic structure of the interface region, which is only a few nanometers in size. We propose and examine the feasibility of a more direct approach to elucidating the ion dynamic by reporting the results of equilibrium and non-equilibrium molecular dynamics calculations in which an iodine ion is created at the interface between water and CCl4 by photodissociation of an adsorbed I-2(-). In this paper, we describe the model, examine the associated free energy curves and discuss the recombination of the parent molecule and its vibrational relaxation as a competing process for the ion transfer process.