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Pristine, single-crystalline graphene displays a unique collection of remarkable electronic properties that arise from its two-dimensional, honeycomb structure. Using in situ low-energy electron microscopy, we show that when deposited on the (111) surface of Au carbon forms such a structure. The resulting monolayer, epitaxial film is formed by the coalescence of dendritic graphene islands that nucleate at a high density. Over 95% of these islands can be identically aligned with respect to each other and to the Au substrate. Remarkably, the dominant island orientation is not the better lattice-matched 30° rotated orientation but instead one in which the graphene [01] and Au [011] inplane directions are parallel. The epitaxial graphene film is only weakly coupled to the Au surface, which maintains its reconstruction under the slightly p-type doped graphene. The linear electronic dispersion characteristic of free-standing graphene is retained regardless of orientation. That a weakly interacting, nonlattice matched substrate is able to lock graphene into a particular orientation is surprising. This ability, however, makes Au(111) a promising substrate for the growth of single crystalline graphene films. [ABSTRACT FROM AUTHOR]

The article presents a reprint of the article "Graphene: The Magic of Flat Carbon," by Konstantin S. Novoselov, which appeared in the 2009 issue of "ECS Transactions." It explores graphene as a two-dimensional atomic crystal and a mono-atomically thin two-dimensional (2D) film of carbon atoms organized laterally in a honeycomb benzene ring-like structure. It says that graphene is used as the base material for an electronic circuitry envisaged to comprise of nanometer-sized quantum dots.

We study the structural and electronic properties of silicene on solid Ar(111) substrate using ab initio calculations. We demonstrate that due to weak interaction, quasi-freestanding silicene is realized in this system. The small binding energy of only meV per Si atom also indicates the possibility to separate silicene from the solid Ar(111) substrate. In addition, a band gap of 11 meV and a significant splitting of the energy levels due to spin-orbit coupling are observed. [ABSTRACT FROM AUTHOR]