One-dimensional metal–organic chains often possess a complex magnetic structure susceptible to modification by alteration of their chemical composition. The possibility to tune their magnetic properties provides an interesting playground to explore quasi-particle interactions in low-dimensional systems. Despite the great effort invested so far, a detailed understanding of the interactions governing the electronic and magnetic properties of the low-dimensional systems is still incomplete. One of the reasons is the limited ability to characterize their magnetic properties at the atomic scale. Here, we provide a comprehensive study of the magnetic properties of metal–organic one-dimensional (1D) coordination polymers consisting of 2,5-diamino-1,4-benzoquinonediimine ligands coordinated with Co or Cr atoms synthesized under ultrahigh-vacuum conditions on a Au(111) surface. A combination of integral X-ray spectroscopy with local-probe inelastic electron tunneling spectroscopy corroborated by multiplet analysis, density functional theory, and inelastic electron tunneling simulations enables us to obtain essential information about their magnetic structures, including the spin magnitude and orientation at the magnetic atoms, as well as the magnetic anisotropy.
Swiss National Science Foundation (Grants P300P2_177755 and 173720), University of Zürich Research Priority Program LightChEC Spanish PID2019-103910GB-I00, funded by MCIN/AEI/10.13039/501100011033/and FEDER Una manera de hacer Europa, as well as GIU18/138 by Universidad del País Vasco UPV/EHU, IT-1246-19 and IT-1260-19 by Gobierno Vasco, Praemium Academie of the Czech Academy of Sciences, Czech Science Foundation projects no. 20-13692X, 20-18741S, and 21-09766S. Czech Nanolab Research Infrastructure supported by MEYS CR project no. LM2018110.