PREROUGHENING, DIFFUSION, AND GROWTH OF A FCC(111) SURFACE

Preroughening of close-packed fcc(111) surfaces, found in rare gas sol ids, is an interesting but poorly characterized phase transition. We i ntroduce a restricted solid-on-solid model, which describes it. Using mostly Monte Carlo, we study both statics, including critical behavior and scattering properties, and dynamics, including surface diffusion and growth. In antiphase scattering, it is shown that preroughening wi ll generally show up at most as a dip. Surface growth is predicted to be continuous at preroughening, where surface self-diffusion should al so drop. The physical mechanism leading to preroughening on rare gas s urfaces is analyzed and identified in the step-step elastic repulsion.