Self-Consistent Theory of Surface Phonon Dispersion Curves at the (110) Surface of Aluminum

Abstract

Considerable progress has been made in recent years in the experimental determination of surface phonon dispersion curves for metals by inelastic helium atom scattering [1] and by electron energy loss spectroscopy [2]. Relatively little progress has been made, however, in the first-principles calculation of surface phonon dispersion curves for metals. In the pseudopotential perturbation-theoretic calculations of CALANDRA et al.[3] for alkali metal surfaces, the ground state and response properties of the electronic subsystem were calculated using the infinite-barrier model (IBM) for the electron wave functions. Surface phonon dispersion curves were then calculated from the response function. Although this procedure is relatively simple, it does not provide a self-consistent treatment of the metal surface. In a different approach HO and BOHNEN [4] used the local density approximation (LDA) to density functional theory and the frozen-phonon method to calculate the surface phonon frequencies for Al(110) at a few high symmetry points on the boundary of the surface Brillouin zone. They then employed a force constant model to interpolate between these points and the origin and thus obtain surface phonon dispersion curves. Clearly, such a calculation is a hybrid and not a bona fide first-principles calculation of surface phonon dispersion curves.KeywordsLocal Density ApproximationElectron Energy Loss SpectroscopyPhonon DispersionDynamical MatrixPhonon Dispersion CurveThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.