Magnetic properties and spin-spin interaction in nitrogen-doped fullerene nanostructures

Fullerenes encapsulating nitrogen atoms, also called endohedral fullerenes, are spin active. The magnetic moment is localized on the nitrogen atom, but the spin dynamics is shown to be governed by the coupling to the fullerene orbitals, allowing for an indirect spin manipulation by acting on the fullerene and its environment. Here, for multiple ground-state endohedral fullerenes, the inter-fullerene spin-spin interactions are investigated with a focus on the effects of stable geometric arrangements (linear, triangular, and more complex arrangements). Performing full ab initio simulations, we aim at an understanding of how the interactions between spins depend on both the structural features of the fullerene molecules and their molecular orbitals. Our computational study explores the role of spin exchange interactions, potential spin frustration, and how these phenomena can be manipulated to achieve desired magnetic behaviors; thus, it can guide the design of new materials for spintronic devices, quantum information processing, and other applications that require control over spin-spin interactions is decisive.