Investigation of transport across an immiscible liquid/liquid interface - Electrochemical and second harmonic generation studies

An electrochemical investigation of the transport of the crown ether 4'-nitrobenzo-15-crown-5 across a water/1,2-dichloroethane interface showed that the crown ether did not cross the interface but the complex formed by the crown ether with Na+ did transfer, the peak transfer current increased with increasing [Na+] until all the crown ether was complexed. The in situ interfacial second harmonic generation experiment indicates that, in the absence of Na+, the crown ether is oriented and ordered by the electric field at the interface. The sodium coronate shows a more complex behaviour at the interface.