A Simple Model for the Surface Phenomena

The simplicity of the present model consists in the construction of the Hamiltonian based on the models of quasi-harmonic oscillators coupled to quasi-free electrons with the effective parameters which are estimated by means of the pseudoharmonic approach and coherent potential approximation, respectively. The geometry of a sample is determined by the topological disorder at the surface reflecting the surface roughness. The model is discussed in connection with the friction related to the melting and pre-melting phenomena. The backscattering of electrons seems to be a testing tool useful not only for decorated surfaces but also for quasi-liquid layers.