Density functional calculation of semiconductor surface phonons

Vibrations on a surface directly reflect the atomic arrangement and the force constants between the atoms in the outermost layers of a solid. Semiconductor surfaces are particularly interesting, because of the covalent bonding nature of the bulk material. A thorough analysis of the vibrational modes therefore contributes essentially to a better understanding of the driving forces and processes that determine the geometry and the electronic properties in the surface region. Tn this report, we summarize recent developments in density-functional theory which have substantially intensified theoretical investigation of semiconductor surface dynamics. We briefly describe the conceptional details of nb initio linear-response theory, molecular-dynamics simulations, and frozen-phonon-like approaches which are the most successful computational schemes applied in the past few years. A collection of the most important results obtained on the basis of such computations will demonstrate how density-functional calculations of this kind contribute to a clear and detailed insight into the structural and dynamical properties of semiconductor surfaces. (C) 1999 Elsevier Science B.V. All rights reserved.