Atomic geometry, electronic structure, and vibrational properties of the Ge(001)(2×1) surface

Abstract

Results of ab initio pseudopotential calculations for atomic geometry, bonding, and electronic band structure of the Ge(001)(2$\ifmmode\times\else\texttimes\fi{}$1) surface are presented and discussed. These are then used as input for calculations of the vibrational properties of this surface within the adiabatic bond-charge model. The phonon spectrum thus obtained is compared in detail with that of the Si(001)(2$\ifmmode\times\else\texttimes\fi{}$1) surface. The spectra and atomic displacement patterns are found to show marked qualitative similarities, while quantitative differences are attributed to the mass difference between Si and Ge atoms.