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arXiv · 1507.07670

Substrate-induced structures of bismuth adsorption on graphene: a first principle study

S. Y. Lin·S. L. Chang·H. H. Chen·S. H. Su·J. C. A. Huang·M. -F. Lin
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Abstract

The geometric and electronic properties of Bi-adsorbed monolayer graphene, enriched by the strong effect of substrate, are investigated by first-principles calculations. The six-layered substrate, corrugated buffer layer, and slightly deformed monolayer graphene are all simulated. Adatom arrangements are thoroughly studied by analyzing the ground-state energies, bismuth adsorption energies, and Bi-Bi interaction energies of different adatom heights, inter-adatom distance, adsorption sites, and hexagonal positions. A hexagonal array of Bi atoms is dominated by the interactions between the buffer layer and the monolayer graphene. An increase in temperature can overcome a $\sim 50$ meV energy barrier and induce triangular and rectangular nanoclusters. The most stable and metastable structures agree with the scanning tunneling microscopy measurements. The density of states exhibits a finite value at the Fermi level, a dip at $\sim -0.2$ eV, and a peak at $\sim -0.6$ eV, as observed in the experimental measurements of the tunneling conductance.

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S. Y. Lin, S. L. Chang, H. H. Chen, S. H. Su, J. C. A. Huang, M. -F. Lin. 2015-07-28. Substrate-induced structures of bismuth adsorption on graphene: a first principle study. https://doi.org/10.1039/c6cp03406c

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