Emergence of π-Magnetism in Fused Aza-Triangulenes: Symmetry and Charge Transfer Effects

• DOI: 10.1021/acs.nanolett.3c02586
• Publication Date: 2023-10-23T12:55:51Z
• Authors: Jan Patrick Calup...; Alejandro Berdonc...; Fernando Aguilar-...; Manuel Vilas-Varela; Diego Peña; David Casanova; Martina Corso; Dimas G. de Oteyza; Tao Wang
• Keywords: Magnetism; Molecular symmetry; Open shell; Carbon fibers; Partial charge

On-surface synthesis has paved the way toward fabrication and characterization of conjugated carbon-based molecular materials that exhibit π-magnetism such as triangulenes. Aza-triangulene, a nitrogen-substituted derivative, was recently shown to display rich on-surface chemistry, offering an ideal platform investigate structure-property relations regarding spin-selective charge transfer magnetic fingerprints. Herein, we study electronic changes upon fusion single molecules into larger dimeric derivatives. We show closed-shell structure aza-triangulene on Ag(111) leads dimers covalently coupled through sterically accessible carbon atoms. Meanwhile, its open-shell Au(111) coupling via atoms displaying high spin density, resulting in symmetric or asymmetric products. Interestingly, whereas all similar properties, only ones fingerprints due transfer. These results expose clear relationships among symmetry, transfer, states π-conjugated nanostructures.