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arXiv · 0901.2969

DFT study of Pt-induced Ge(001) reconstructions

Danny E. P. Vanpoucke·Geert Brocks
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Abstract

Pt deposited on a Ge(001) surface spontaneously forms nanowire arrays. These nanowires are thermodynamically stable and can be hundreds of atoms long. The nanowires only occur on a reconstructed Pt-Ge-surface where they fill the troughs between the dimer rows on the surface. This unique connection between the nanowires and the underlying substrate make a thorough understanding of the latter necessary for understanding the growth of the nanowires. In this paper we study possible surface reconstructions containing 0.25 and 0.5 of a monolayer of Pt. Comparison of calculated STM images to experimental STM images of the surface reconstruction reveal that the Pt atoms are located in the top layer, creating a structure with rows of alternating Pt-Ge and Ge-Ge dimers in a c(4x2) arrangement. Our results also show that Pt atoms in the second or third layer can not be responsible for the experimentally observed STM images.

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Danny E. P. Vanpoucke, Geert Brocks. 2011-02-01. DFT study of Pt-induced Ge(001) reconstructions. https://doi.org/10.1103/physrevb.81.035333

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