SEGREGATION KINETIC SIMULATION AND SEGREGATION ENERGY DETERMINATION ON A CUAG(111) ALLOY

Using a method based on the kinetic tight binding Ising model (KTBIM), the segregation energy on the (111) face of a CuAg 0.45 at% alloy, is derived as a function of surface coverage, from segregation kinetics measured at 763 K. Nearly the same segregation energy value as from eq uilibrium experiments is obtained. Besides, it is shown that a surface size effect term, proportional to the square of the surface concentra tion, has to be introduced in the segregation energy, in order to take into account the surface strain energy which occurs in the first laye r when the silver atoms segregate at the surface.