biostudies-literatureHenriques JSwiss National Science FoundationMinisterio de Ciencia e Innovaci?nEuropean CommissionFunda??o para a Ci?ncia e a TecnologiaGeneralitat Valenciana3355-3360https://www.ebi.ac.uk/biostudies/studies/S-EPMC10958603biostudies-literatureUnknown24(11)Motivated by recent experimental breakthroughs, we propose a strategy for designing two-dimensional spin-lattices with competing interactions that lead to nontrivial emergent quantum states. We consider <i>S</i> = ¹/₂ nanographenes with <i>C</i>₃ symmetry as building blocks, and we leverage the potential to control both the sign and the strength of exchange with first neighbors to build a family of spin models. Specifically, we consider the case of a Heisenberg model in a triangle-decorated honeycomb lattice with competing ferromagnetic and antiferromagnetic interactions whose ratio can be varied in a wide range. On the basis of the exact diagonalization of both Fermionic and spin models, we predict a quantum phase transition between a valence bond crystal Nano lettersDesigner Spin Models in Tunable Two-Dimensional Nanographene Lattices.PMC10958603101079184Prometeo2021/017PTDC/FIS-MAC/2045/2021PID2019-109539GB-C41CIACIF/2021/434PRTR- C1y.I1MFA/2022/045205987CRSII5-205987Ferri-Cortes MFernandez-Rossier JHenriques JfalseDesigner Spin Models in Tunable Two-Dimensional Nanographene Lattices.Motivated by recent experimental breakthroughs, we propose a strategy for designing two-dimensional spin-lattices with competing interactions that lead to nontrivial emergent quantum states. We consider <i>S</i> = ¹/₂ nanographenes with <i>C</i>₃ symmetry as building blocks, and we leverage the potential to control both the sign and the strength of exchange with first neighbors to build a family of spin models. Specifically, we consider the case of a Heisenberg model in a triangle-decorated honeycomb lattice with competing ferromagnetic and antiferromagnetic interactions whose ratio can be varied in a wide range. On the basis of the exact diagonalization of both Fermionic and spin models, we predict a quantum phase transition between a valence bond crystal 2024-01-01T00:00:00Z2024 Mar2025-04-04T20:07:20.046Z2025-04-04T20:07:20.046ZS-EPMC109586033842797510.1021/acs.nanolett.3c04915