Thermodynamics of surface morphology.

Classical thermodynamic descriptions of surfaces treat surface orientation as a thermodynamic degree of freedom and thus allow for the possibility of reversible changes in surface morphology as a function of temperature or impurity concentration. The existence of these transitions has been confirmed experimentally. Advances in surface diffraction and imaging techniques now make it possible to characterize such transitions quantitatively in terms of the atomic structure, and particularly in terms of the behavior of steps on surfaces. Statistical mechanical models can be used to analyze the observations to determine the fundamental energetic parameters governing the observed thermodynamic behavior.