Electronic and Vibrational Properties of On-Surface Synthesized Gulf-Edged Chiral Graphene Nanoribbons

Xuanchen Li; Amogh Kinikar; Vikas Sharma; Andres Ortega Guerrero; Riya Sebait; George F. S. Whitehead; Mickael Lucien Perrin; Carlo A. Pignedoli; Roman Fasel; Ashok Keerthi; Gabriela Borin Barin

arXiv · 2604.21796

Electronic and Vibrational Properties of On-Surface Synthesized Gulf-Edged Chiral Graphene Nanoribbons

Xuanchen Li·Amogh Kinikar·Vikas Sharma·Andres Ortega Guerrero·Riya Sebait·George F. S. Whitehead·Mickael Lucien Perrin·Carlo A. Pignedoli·Roman Fasel·Ashok Keerthi·Gabriela Borin Barin

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Abstract

On-surface synthesis enables graphene nanoribbons (GNRs) with atomic precision, but the structural diversity of chiral GNRs remains constrained by the limited range of precursor architectures. Here, we design a trisnaphthalene-based diiodo precursor and use it to synthesize a gulf-edged (4,2,7)-chGNR on Au(111). Scanning tunneling microscopy and bond-resolved non-contact atomic force microscopy establish the atomically precise ribbon structure, while scanning tunneling spectroscopy and periodic density functional theory calculations identify a closed-shell semiconducting state with an experimental band gap of 1.8 eV. Raman spectroscopy, supported by vibrational calculations, resolves a mode localized predominantly at the gulf-edge C-H groups and reveals rapid spectral degradation following air exposure. These results demonstrate a precursor-design concept for a distinct chGNR architecture and correlate its atomic structure with its electronic, vibrational, and environmental-response properties.

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Xuanchen Li, Amogh Kinikar, Vikas Sharma, Andres Ortega Guerrero, Riya Sebait, George F. S. Whitehead, Mickael Lucien Perrin, Carlo A. Pignedoli, Roman Fasel, Ashok Keerthi, Gabriela Borin Barin. 2026-04-23. Electronic and Vibrational Properties of On-Surface Synthesized Gulf-Edged Chiral Graphene Nanoribbons. https://arxiv.org/abs/2604.21796

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