Temperature dependence of the surface diffusion coefficient of K atoms on Pd{111} measured with PEEM

The surface diffusion of potassium on Pd{111} has been studied in real time as a function of temperature between 100 and 190 K in the limit of zero concentration (Θ < 0.05 ML) using photoelectron emission microscopy (PEEM). Very fast migration of K atoms was observed on flat, quasi-one-dimensional regions of the surface between the step bunches. The temperature dependence of the diffusion coefficient indicates an activated process with an energy barrier of 66 ± 11 meV