First-principles calculations indicated that the ground state for Ga adsorption on Al(100) was a surface with local unit coverage. In the case of Ga-coated Al(100), the bridge diffusion barrier for Al was large, but the Al-Ga exchange barrier was zero. The resultant incorporation of randomly deposited Al, into the Ga over-layer, produced a percolation network that was efficiently re-coated with Ga atoms. On the basis of the estimated energetics, the occurrence of rough surface growth was predicted at all temperatures.

V.Fiorentini, D.Fois, S.Oppo: Physical Review Letters, 1996, 77[4], 695-8