Generalized model for interface description

In this paper a complete formalism for interface description is presented. The interfaces to be described may be continuous or granular and are characterized by a few very general parameters: the coverable part of the surface; the island generating function depending on the crystallographic symmetry of the islands or clusters; the maximal height an island may reach before it is touching another, the distribution of island heights and the concentrations of the evaporated elements. All these parameters may depend on coverage, time, temperature etc. allowing for the description of many phenomena which affect the island shape. The formalism is versatile and the field of its potential applications is large and may grow. It is well suited to describe almost everything which happens at the surface: the growth of binary systems, alloys, alloying, diffusion, clusters etc. II is naturally well suited for describing the intensities measured by spectroscopies. The formalism is explicitly extended to these techniques. A consequence of the generalized description is to break down some of the well accepted ideas in this field like: premonolayer breaks, the occurrence of breaks only if the growth is of a layer by layer type and the ability of such techniques to describe, without any other data, growth modes. Finally new applications are suggested for spectroscopies: adsorbate surface roughening and multilayer growth monitoring. (C) 1998 Elsevier Science B.V. All rights reserved.