Nanostructuring of Dysprosocenium Single-Ion Magnets through Encapsulation in MOFs: A Promising Approach to Achieve High Axiality and Ambient Stability with Long-Range Ordering

Implementing magnetic bistability in single-molecule magnets (SMMs) for quantum technologies requires precise nanostructuring, spatial organization, and environmental stabilization of magnetic centers. Here, we report the first encapsulation of the lanthanide-based <b>[Dy(Cp*)</b>_<b>2</b><b>]</b>^<b>+</b> SMM in three mesoporous diamagnetic MOFs─NU-1000, PCN-222-Zn, and MOF-177─to design hybrid magnetic structures with long-range ordering. An integrated approach combining DFT and AIMD simulations was carried out to unravel the structure, dynamics, stability, and nature of host-guest interactions in hybrid assemblies. Geometry optimizations show that the triangular pores of NU-1000 and PCN-222-Zn and the diamond pores of MOF-177 adequately accommodate <b>[Dy(Cp*)</b>_<b>2</b><b>]</b>^<b>+</b> without perturbing its local structure. Charge difference density and energy decomposition analysis reveal strong dispersion-driven host-guest interactions as the key stabilizing factor. CASSCF-SO-computed ab initio blockade barriers for all three [Dy(Cp*)₂]⁺@MOFs models show a giant barrier >1200 cm^-1, which is on par with <b>[Dy(Cp*)</b>_<b>2</b><b>]</b>^<b>+</b>. CASSCF-SO calculations on the AIMD trajectories of <b>[Dy(Cp*)₂]⁺</b>@NU-1000 (1-16 ps) reveal that the structural and magnetic properties remain unchanged post-encapsulation. Spin-vibronic analysis shows that the strongest spin-vibronic mode is attenuated by ∼30% upon encapsulation. Overall, our findings establish mesoporous MOFs as a promising avenue for stabilizing Ln-based SIMs with reduced vibrational decoherence, enabling long-range ordering and scalable integration of SMMs for futuristic applications.