Role of the Magnetic Anisotropy in Atomic- Spin Sensing of 1 D Molecular Chains

One-dimensional metal-organic chains often possess a complex magnetic structure susceptible to modifica-tion by alteration of their chemical composition. The possibility to tune their magnetic properties provides an interest i n g playground to explore quasi-particle interactions in low-dimensional systems. Despite the great effort invested so far, a detailed understand i n g of the interactions governing the electronic and magnetic properties of the low-dimensional systems is st i l l incomplete. One of the reasons is the limited abi l i t y 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) coordina-tion polymers consisting of 2,5-diamino-1,4-benzoquinonedu mine 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 magneti c atoms, as wel l as the magnetic anisotropy.