The growth of ultra-thin films of γ-Fe on (100) Cu was investigated by using density-functional calculations. It was shown that the formation of a surfactant Cu layer on top of growing Fe films was energetically favored over both clean Fe surfaces, or the formation of ordered surface alloys. The exchange process which led to the incorporation of Fe atoms in, or below, the Cu top layer was characterized by a barrier of 1.45eV per Fe-atom. It was therefore kinetically hindered at low temperatures.

Growth of Face-Centered-Cubic Fe Films on Cu(100) - Interdiffusion, Surfactant Effects, and Island Formation. D.Spišák, J.Hafner: Physical Review B, 2001, 64[20], 205422 (11pp)