• 文献标题:   Magnetic Interactions Between Radical Pairs in Chiral Graphene Nanoribbons
  • 文献类型:   Article
  • 作  者:   WANG T, SANZ S, CASTROESTEBAN J, LAWRENCE J, BERDONCESLAYUNTA A, MOHAMMED MSG, VILASVARELA M, CORSO M, PENA D, FREDERIKSEN T, DE OTEYZA DG
  • 作者关键词:   magnetism, spin interaction, graphene nanoribbon, heteroatom substitution, scanning tunneling microscopy, density functional theory, meanfield hubbard model
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:  
  • 被引频次:   15
  • DOI:   10.1021/acs.nanolett.1c03578 EA DEC 2021
  • 出版年:   2022

▎ 摘  要

Open-shell graphene nanoribbons have become promising candidates for future applications, including quantum technologies. Here, we characterize magnetic states hosted by chiral graphene nanoribbons (chGNRs). The substitution of a hydrogen atom at the chGNR edge by a ketone effectively adds one p(z) electron to the pi-electron network, producing an unpaired pi-radical. A similar scenario occurs for regular ketone-functionalized chGNRs in which one ketone is missing. Two such radical states can interact via exchange coupling, and we study those interactions as a function of their relative position, which includes a remarkable dependence on the chirality, as well as on the nature of the surrounding ribbon, that is, with or without ketone functionalization. Besides, we determine the parameters whereby this type of system with oxygen heteroatoms can be adequately described within the widely used mean-field Hubbard model. Altogether, we provide insight to both theoretically model and devise GNR-based nanostructures with tunable magnetic properties.