  Coupling between a magnetic impurity and an external bath can give rise to
many-body quantum phenomena, including Kondo and Hund's impurity states in
metals, and Yu-Shiba-Rusinov states in superconductors. While advances have
been made in probing the magnetic properties of d-shell impurities on surfaces,
the confinement of f orbitals makes them difficult to access directly. Here we
show that a 4f driven Kondo resonance can be modulated spatially by asymmetric
coupling between a metallic surface and a molecule containing a 4f-like moment.
Strong hybridisation of dysprosium double-decker phthalocyanine with Cu(001)
induces Kondo screening of the central magnetic moment. Misalignment between
the symmetry axes of the molecule and the surface induces asymmetry in the
molecule's electronic structure, spatially mediating electronic access to the
magnetic moment through the Kondo resonance. This work demonstrates the
important role that molecular ligands play in mediating electronic and magnetic
coupling and in accessing many-body quantum states.
