Altering Spin Distribution of Tb₂Pc₃ via Molecular Chirality Manipulation

Manipulating the chirality of the spin-polarized electronic state is pivotal for understanding many unusual quantum spin phenomena, but it has not been achieved at the single-molecule level. Here, using scanning tunneling microscopy and spectroscopy (STM/STS), we successfully manipulate the chirality of spin distribution in a triple-decker single-molecule magnet tris(phthalocyaninato)bis(terbium(III)) (Tb₂Pc₃), which is evaporated on a Pb(111) substrate via molecular beam epitaxy. The otherwise achiral Tb₂Pc₃ becomes chiral after being embedded into the self-assembled monolayer films of bis(phthalocyaninato)terbium(III) (TbPc₂). The chirality of the spin distribution in Tb₂Pc₃ is manifested via the spatial mapping of its Kondo resonance state from its ligand orbital. Our first-principles calculations revealed that the spin and molecular chirality are associated with a small rotation followed by a structural distortion of the top Pc, consistent with the experimental observation. By constructing tailored molecular clusters with the STM tip, a single Tb₂Pc₃ molecule can be manipulated among achiral and differently handed chiral configurations of spin distributions reversibly. This paves the way for designing chiral spin enantiomers for fundamental studies and developing functional spintronic devices.