Imaging the Single‐Electron Ln–Ln Bonding Orbital in a Dimetallofullerene Molecular Magnet

Chemically robust single‐molecule magnets (SMMs) with sufficiently high blocking temperatures TB are among the key building blocks for the realization of molecular spintronic or quantum computing devices. Such device applications require access to the magnetic system of a SMM molecule by means of electronic transport, which primarily depends on the interaction of magnetic orbitals with the electronic states of the metallic electrodes. Scanning tunneling microscopy in combination with ab initio calculations allows to directly address the unoccupied component of the single‐electron molecular orbital that mediates the ferromagnetic exchange coupling between two 4f ions within a lanthanide endohedral dimetallofullerene deposited on a graphene surface. The single‐electron metal–metal bond provides a direct access to the molecule's magnetic system in the transport experiments, paving the way for investigation and controlled manipulation of the spin system of individual dimetallofullerene SMMs, essential for molecular spintronics. The single‐electron bond in lanthanide (Ln) dimetallofullerene molecular magnets mediates the ferromagnetic exchange between both Ln ions, leading to exceptional high blocking temperatures. Using scanning tunneling spectroscopy, this work demonstrates electronic transport through its unoccupied component in individual Ln2@C80(CH2Ph) complexes. The results pave the way for the investigation of the spin system of individual dimetallofullerene molecular magnets.