Abstract
The role of self-consistency and of the atomic distortions in determining the electronic structure of the cleavage surfaces of GaAs and ZnSe has been investigated using the layer method and an iterative tight-binding approach, which takes account of the difference between the surface and bulk electronic configurations. Several surface bands and resonances are identified near the gaps and empty lenses of the projected bulk band-structure and their sensitivity to the modifications of the surface potential are discussed. In the case of GaAs the inclusion of the atomic distortions at the surface is essential in order to obtain theoretical results in reasonable agreement with the experimental data. For ZnSe the available experimental information does not permit discrimination between the ideal and distorted configuration of the surface atoms, in spite of the sensitivity of the occupied surface states to the atomic displacements.