Unusually High-Spin Fe₁₂C₁₂^- Metallo-Carbohedrene Clusters

Ferromagnets constructed from nanometals of atomic precision are important for innovative advances in information storage, energy conversion, and spintronic microdevices. Considerable success has been achieved in designing molecular magnets, which, however, are challenging in preparation and may suffer from drawbacks on the incompatibility of high stability and strong ferromagnetism. Utilizing a state-of-the-art self-developed mass spectrometer and a homemade laser vaporization source, we have achieved a highly efficient preparation of pure iron clusters, and here, we report the finding of a strongly ferromagnetic metal-carbon cluster, Fe₁₂C₁₂^-, simply by reacting the Fe^- clusters with acetylene in proper conditions. The unique stability of this ferromagnetic Fe₁₂C₁₂^- cluster is rooted in a plumb-bob structure pertaining to Jahn-Teller distortion. We classify Fe₁₂C₁₂^- as a new member of metallo-carbohedrenes and elucidate its structural stability mechanism as well as its soft-landing deposition and magnetization measurements, providing promise for the exploration of potential applications.