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Surface Reconstructions and Bonding via the Electron Localization Function: The Case of Si(001)

L. De Santis·R. Resta
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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.

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L. De Santis, R. Resta. 1999-03-19. Surface Reconstructions and Bonding via the Electron Localization Function: The Case of Si(001). https://doi.org/10.1016/s0038-1098(99)00138-6

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