Engineering giant magnetic anisotropy in single-molecule magnets by dimerizing heavy transition-metal atoms

Search for single-molecule magnets with large magnetic anisotropy energy (MAE) is essential for the development of molecular spintronics devices used at room temperature. Through systematic first-principles calculations, we found that an Os-Os or Ir-Ir dimer embedded in the (5,5'-Br2-Salophen) molecule gives rise to large MAE of 41.6 or 51.4 meV which is large enough to hold the spin orientation at room temperature. Analysis of electronic structures reveals that the top Os and Ir atoms are most responsible for the spin moments and large MAEs of the molecules.