Ambient-Stable Electroactive Graphene Nanoribbons: A Comprehensive Analysis of Distance, Degree, Energetics and ¹³ C NMR Signals

Introduction: Topological indices serve as mathematical descriptors for chemical structures, playing a crucial role in elucidating the physicochemical characteristics of compounds. Ambient- stable electroactive graphene nanoribbons are air-stable, electronically tunable and easily fabricated nanostructures, formed by the elongation of nanographene ribbon segments. This study aimed to develop precise topological formulations for three types of ambient-stable electroactive graphene nanoribbons (AEGNR) using graph-theoretical structural measures, and to evaluate their energetic properties along with their 13C NMR spectral characteristics. Methods: The study employs the cut method, which is based on the Djoković-Winkler θ relation, to calculate topological indices. Results: In this article, we evaluated selected spectral and energetic properties of AEGNR variants. Discussion: The computed topological indices based on distance and vertex degree could provide important chemical insights into the properties of AEGNR(l). Conclusions: We developed exact mathematical expressions for bond-additive molecular descriptors corresponding to three types of ambient-stable electroactive graphene nanoribbons (AEGNRs). An evaluation of HOMO-LUMO energy gaps was also performed for the AEGNR(l) chains.