Issue 56, 2020

Metallic bands in chevron-type polyacenes

Abstract

We present electronic structure calculations based on a single-parameter plane wave expansion method for basic graphene building blocks, namely n-oligophenylenes and n-oligoacenes, revealing excellent agreement with density-functional theory. When oligophenylene molecules are joined through meta (zigzag) or ortho (chevron) junctions, the resulting molecular dimers and polymers exhibit a semiconducting character. While zigzag dimers of oligoacenes also exhibit gapped electronic structures, their chevron-phase features a sharp metallic band at the Fermi energy. This zero-point-energy state, which transforms into Dirac-like band in chevron polymers, survives at the outer elbows of the dimer irrespective of the molecular length, and has the same origin as reported for the polyacetylene and topologically induced edge states at edge-decorated graphene nanoribbons. These findings assist the engineering of topological electronic states at the molecular level and complement the toolbox of quantum phases in carbon-based nanostructures.

Graphical abstract: Metallic bands in chevron-type polyacenes

Supplementary files

Article information

Article type
Paper
Submitted
09 Jul 2020
Accepted
04 Sep 2020
First published
14 Sep 2020
This article is Open Access
Creative Commons BY license

RSC Adv., 2020,10, 33844-33850

Metallic bands in chevron-type polyacenes

M. A. Kher-Elden, I. Piquero-Zulaica, K. M. Abd El-Aziz, J. E. Ortega and Z. M. Abd El-Fattah, RSC Adv., 2020, 10, 33844 DOI: 10.1039/D0RA06007K

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements