EXACT RESULTS FOR ADATOM MIGRATION ON A RECONSTRUCTIVE SURFACE

The influence of surface reconstruction on adatom diffusion is investi gated in the framework of anisotropic Ising model. The exact expressio ns for diffusion coefficient are obtained for an ordered and disordere d phase of the surface. Dependences of the diffusion coefficient on th e adatom concentration and interaction parameters are discussed. It is shown that the region of critical slow down of the diffusion is extre mely small. Consequently, it is hard to test predicted dependences exp erimentally or by numerical simulation. We discuss shortly possible ex perimental technique for investigation of the critical behaviour of su rface diffusion coefficient.