2022/02/10 by Nesrine Shaiek, Hassan Denawi, Shaiek, Nesrine +20
Chemistry · Engineering · Physics and Astronomy · #Ab initio #Advanced Condensed Matter Physics #Atomic physics #Brillouin zone #Chemistry #Computational chemistry #Condensed matter physics #Density functional theory #Electron #Electronic structure #FOS: Physical sciences #Fermi level #Ferromagnetism #Ground state #Materials Science (cond-mat.mtrl-sci) #Materials science #Monolayer #Nanotechnology #Nuclear magnetic resonance #Other Condensed Matter (cond-mat.other) #Physics #Quantum and electron transport phenomena #Scanning tunneling microscope #Surface Chemistry and Catalysis #X-ray photoelectron spectroscopy #cond-mat.mtrl-sci #cond-mat.other
paper · pdf · doi:10.48550/arxiv.2202.04867
published in arXiv (Cornell University) (Cornell University) · 17 pages (main text) plus 23 pages (supplementary information), 8 plus 13 figures
arxiv created 2022/02/10 · openalex publication_date 2022/02/10 · arxiv updated 2022/02/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We report on the successful on-surface synthesis of metal-organic covalent coordination networks with a dense Kagome lattice of metallic centers. In the case of Mn centers ab-initio calculations show that the adsorbed monolayer on Ag(111) has all the characteristic features of a strictly two-dimensional (2D) ferromagnetic Kagome metal. Tetrahydroxyquinone (THQ) and metal atoms (M=Cu or Mn) are co-deposited on the Ag(111) substrate to build well-ordered 2D lattices M3C6O6. The surface is studied by scanning tunneling microscopy (STM), low energy electron diffraction (LEED) and X-ray photoelectron spectroscopy (XPS) to optimize the growth conditions like fluxes and temperatures. The details of the atomic, electronic and magnetic structures are clarified by density functional theory (DFT) calculations. XPS and DFT reveal a Cu+ charge state and no local magnetic moments for the Cu-organic network. For the Mn-organic network, we find the charge state Mn2+ and a local spin S=5/2. Charge transfer stabilizes the Cu+ and Mn2+ charge states. We find two different modifications of the M3C6O6 lattice. DFT calculations which neglect the small spin-orbit coupling show a Dirac point, i.e. a band crossing with linear electron dispersion at the K-point of the Brillouin zone. This Dirac point is at the Fermi level if there is no charge transfer but drops by 100 meV if electron doping of Cu3C6O6 on Ag(111) surface is acknowledged. We predict the magnetic couplings of an isolated M3C6O6 monolayer to be short range and antiferromagnetic leading to high frustration at the Kagome lattice and a tendency towards a spin-liquid ground state. In the case of hole transfer from the substrates ferromagnetic ordering is introduced, making M3C6O6 an interesting candidate for the quantum anomalous Hall effect.