Inducing antiferromagnetism in nanographenes via tuning of edge state interactions of closed-shell precursors

Antiferromagnetic graphene nanoribbons (AFM-GNRs) hold significant potential in spintronics and quantum computing. However, achieving high spin-density AFM-GNRs remains a challenge. Herein, we report two unconventional routes for producing AFM-GNRs from closed-shell rhombene units (RUs), including (i) applying compression on the bonds between RUs to enhance the interunit Coulomb repulsion and (ii) merging the edges of RUs to release the confined spin states. Density functional theory and tight-binding calculations demonstrate the spin distribution and spin generation mechanisms for both routes.