Migration of the subsurface C impurity in Pd(111) -: art. no. 033407

The diffusion of subsurface impurities such as C in palladium surfaces of (111) orientation has been studied under the generalized gradient approximation combining a pseudopotential plane wave scheme as implemented in the VASP code with the aim of providing a better understanding between theoretical and experimental behavior. We analyze the stability of different subsurface sites, the energy barriers separating them from neighboring sites and the corresponding energy profiles. It is found that the most stable sites are located between the first and second surface layers, in good agreement with the experiments.