Surface Reconstructions and Bonding via the Electron Localization Function: The Case of Si(001)
arXiv:cond-mat/9903303 · doi:10.1016/S0038-1098(99)00138-6
Abstract
The bonding pattern of a covalent semiconductor is disrupted when a surface is cut while keeping a rigid (truncated bulk) geometry. The covalent bonds are partly reformed (with a sizeable energy gain) when reconstruction is allowed. We show that the ``electron localization function'' (ELF)---applied within a first--principles pseudopotential framework---provides un unprecedented insight into the bonding mechanisms. In the unreconstructed surface one detects a partly metallic character, which disappears upon reconstruction. In the surface reformed bonds, the ELF sharply visualizes strongly paired electrons, similar in character to those of the bulk bonds.
6 pages, 8 included figures; revtex file. To appear on Solid State Communications