Tailoring the magnetism of 4f rare-earth atom lattices formed by metal-organic coordination

A single atom with long spin lifetime represents the prototype of the smallest bit for data storage. So far, single atom magnets have been obtained by adsorbing a 4f rare earth atom onto a well-defined site at surfaces, or by inserting it into custom-designed molecular frames. Here we propose a different approach. By combining atom adsorption at surfaces and 2D coordination with organic ligands, we aim at realizing a lattice of rare-earth single atom magnets with tunable magnetic properties. Coordination with tetraphenyl-dicarbonitrile molecules provides high-symmetry C5v crystal field, while the use of graphene as substrate minimizes spin-electron and spin-phonon scattering. The choice of the rare earth species, with oblate or prolate 4f charge distribution and different total angular moment J, determines the orientation of the magnetization easy axis and the spin lifetime.