The appearance of athermal nuclei of thymine at Au(111) and the shape of current–time transients

The influence of the prepolarisation potential on the kinetics of two-dimensional phase transitions on solid electrodes is demonstrated by numerical simulations based on a coupled system of four differential equations, which explicitly describes the phase transitions. It is shown that the nucleation rate is a sensible function of prepolarisation conditions and cannot be interpreted solely as a function of the applied potential. The simulations can be used for the interpretation of experimental current–time transients obtained in the 12 mmol thymine/0.1 m NaClO4/D2O system. The results indicate that the nucleation on Au(111) and similarly on mercury electrodes obey a mechanism which presupposes subcritical cluster distributions at undersaturation conditions.