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arXiv · 2101.01687

Bandgap evolution in nanographene assemblies

F. Crasto de Lima·A. Fazzio
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Abstract

Recently cycloarene has been experimentally obtained in a self-assembled structure, forming graphene-like monoatomic layered systems. Here, we establish the bandgap engineering/prediction in cycloarene assemblies within a combination of density functional theory and tight-binding Hamiltonians. Our results show a weak dependence of the gap with the assembly geometry, contrasting a strong dependence with the inter-molecule bond density. We derived a effective model that allows the interpretation of the arising energy gap for general particle-hole symmetric molecular arranges based on inter-molecular bond strength.

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F. Crasto de Lima, A. Fazzio. 2021-01-05. Bandgap evolution in nanographene assemblies. https://doi.org/10.1039/d1cp01030a

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